The 1975 Pittsburgh Pirates season was the 94th in the history of the franchise and their 89th in the National League. The Pirates' 92–69 record was good enough to win their fifth National League East title in six seasons by 6 games over their cross-state rivals, the Philadelphia Phillies. The Pirates, however, lost the NLCS to the Cincinnati Reds, three games to none.

Offseason October 22, 1974: Gene Clines was traded by the Pirates to the New York Mets for Duffy Dyer.Duffy Dyer at Baseball Reference January 6, 1975: Nelson Norman was signed as an amateur free agent by the Pirates.Nelson Norman at Baseball Reference February 20, 1975: Albert Williams was signed as an amateur free agent by the Pirates.Albert Williams at Baseball Reference

Regular season September 16, 1975: Rennie Stennett goes 7-for-7 against the Chicago Cubs at Wrigley Field in a 22–0 rout. He is the only MLB player in the 20th century to go 7-for-7 in a 9-inning game.

Season standings

Record vs. opponents

Game log

|- bgcolor="ccffcc" | 1 || April 10 || @ Cubs || 8–4 || Giusti (1–0) || Frailing || — || 19,239 || 1–0 |- bgcolor="ccffcc" | 2 || April 11 || Mets || 4–3 || Demery (1–0) || Baldwin || — || 43,880 || 2–0 |- bgcolor="ccffcc" | 3 || April 13 || Mets || 5–3 || Kison (1–0) || Seaver || — || 14,841 || 3–0 |- bgcolor="ffbbbb" | 4 || April 14 || Cubs || 2–4 || Reuschel || Moose (0–1) || Knowles || 4,780 || 3–1 |- bgcolor="ffbbbb" | 5 || April 16 || Expos || 0–5 || Fryman || Ellis (0–1) || — || 4,807 || 3–2 |- bgcolor="ffbbbb" | 6 || April 17 || Expos || 4–7 || McNally || Reuss (0–1) || — || 5,667 || 3–3 |- bgcolor="ffbbbb" | 7 || April 18 || @ Cardinals || 4–5 (13) || Sadecki || McDowell (0–1) || — || 19,975 || 3–4 |- bgcolor="ccffcc" | 8 || April 19 || @ Cardinals || 7–1 || Rooker (1–0) || Forsch || — || 19,775 || 4–4 |- bgcolor="ccffcc" | 9 || April 20 || @ Cardinals || 5–0 || Brett (1–0) || Denny || Giusti (1) || 20,935 || 5–4 |- bgcolor="ffbbbb" | 10 || April 22 || @ Expos || 3–4 || McNally || Ellis (0–2) || Murray || 5,239 || 5–5 |- bgcolor="ffbbbb" | 11 || April 23 || @ Expos || 0–5 || Fryman || Reuss (0–2) || — || 8,177 || 5–6 |- bgcolor="ccffcc" | 12 || April 25 || Phillies || 3–2 || Kison (2–0) || Carlton || Giusti (2) || 5,726 || 6–6 |- bgcolor="ccffcc" | 13 || April 26 || Phillies || 7–3 || Rooker (2–0) || Twitchell || — || 13,120 || 7–6 |- bgcolor="ccffcc" | 14 || April 27 || Phillies || 2–0 || Ellis (1–2) || Underwood || — || 14,074 || 8–6 |- bgcolor="ffbbbb" | 15 || April 29 || Cardinals || 0–3 || McGlothen || Brett (1–1) || — || 6,319 || 8–7 |- bgcolor="ccffcc" | 16 || April 30 || Cardinals || 5–0 || Reuss (1–2) || Gibson || — || 5,584 || 9–7

|- bgcolor="ffbbbb" | 17 || May 2 || @ Phillies || 5–9 || Twitchell || Kison (2–1) || McGraw || 20,257 || 9–8 |- bgcolor="ffbbbb" | 18 || May 3 || @ Phillies || 2–6 || Underwood || Rooker (2–1) || Garber || — || 9–9 |- bgcolor="ffbbbb" | 19 || May 3 || @ Phillies || 3–4 (11) || McGraw || Hernandez (0–1) || — || 44,501 || 9–10 |- bgcolor="ccffcc" | 20 || May 6 || @ Mets || 2–1 (8) || Brett (2–1) || Seaver || — || 8,257 || 10–10 |- bgcolor="ccffcc" | 21 || May 7 || @ Mets || 6–1 || Reuss (2–2) || Matlack || — || 12,216 || 11–10 |- bgcolor="ccffcc" | 22 || May 8 || @ Mets || 4–2 || Kison (3–1) || Koosman || — || 14,053 || 12–10 |- bgcolor="ccffcc" | 23 || May 9 || Dodgers || 11–3 || Ellis (2–2) || Marshall || Giusti (3) || 16,378 || 13–10 |- bgcolor="ffbbbb" | 24 || May 10 || Dodgers || 2–6 || Rau || Rooker (2–2) || — || 24,870 || 13–11 |- bgcolor="ffbbbb" | 25 || May 11 || Dodgers || 0–7 || Sutton || Brett (2–2) || — || 15,175 || 13–12 |- bgcolor="ccffcc" | 26 || May 13 || Padres || 2–0 || Reuss (3–2) || Spillner || — || 5,482 || 14–12 |- bgcolor="ccffcc" | 27 || May 14 || Padres || 5–4 (11) || McDowell (1–1) || Greif || — || 8,334 || 15–12 |- bgcolor="ccffcc" | 28 || May 16 || @ Dodgers || 3–2 || Giusti (2–0) || Sutton || — || 44,111 || 16–12 |- bgcolor="ffbbbb" | 29 || May 17 || @ Dodgers || 3–4 (10) || Messersmith || Hernandez (0–2) || — || 46,790 || 16–13 |- bgcolor="ccffcc" | 30 || May 18 || @ Dodgers || 7–2 || Brett (3–2) || Hooton || — || 42,013 || 17–13 |- bgcolor="ffbbbb" | 31 || May 19 || @ Giants || 4–6 || Caldwell || Reuss (3–3) || — || 1,795 || 17–14 |- bgcolor="ffbbbb" | 32 || May 20 || @ Giants || 4–12 || Halicki || Ellis (2–3) || — || 1,759 || 17–15 |- bgcolor="ffbbbb" | 33 || May 21 || @ Giants || 1–2 (11) || Barr || Giusti (2–1) || — || 3,513 || 17–16 |- bgcolor="ccffcc" | 34 || May 22 || @ Padres || 4–2 || Rooker (3–2) || Freisleben || Giusti (4) || 9,148 || 18–16 |- bgcolor="ffbbbb" | 35 || May 23 || @ Padres || 3–4 || Frisella || Giusti (2–2) || — || 14,858 || 18–17 |- bgcolor="ffbbbb" | 36 || May 24 || @ Padres || 0–5 || Jones || Reuss (3–4) || — || 22,758 || 18–18 |- bgcolor="ccffcc" | 37 || May 25 || @ Padres || 6–5 (11) || Hernandez (1–2) || Frisella || Demery (1) || 28,778 || 19–18 |- bgcolor="ccffcc" | 38 || May 26 || Astros || 10–2 || Kison (4–1) || Richard || — || 11,126 || 20–18 |- bgcolor="ccffcc" | 39 || May 27 || Astros || 6–5 || Demery (2–0) || Niekro || — || 7,003 || 21–18 |- bgcolor="ccffcc" | 40 || May 28 || Astros || 3–0 || Brett (4–2) || Roberts || — || 7,601 || 22–18 |- bgcolor="ccffcc" | 41 || May 30 || Braves || 2–1 || Reuss (4–4) || Capra || — || 11,565 || 23–18 |- bgcolor="ccffcc" | 42 || May 31 || Braves || 11–4 || Kison (5–1) || Harrison || — || 13,423 || 24–18

|- bgcolor="ffbbbb" | 43 || June 1 || Braves || 2–5 || Niekro || Rooker (3–3) || — || 37,373 || 24–19 |- bgcolor="ffbbbb" | 44 || June 3 || Reds || 4–8 || Nolan || Moose (0–2) || — || 9,438 || 24–20 |- bgcolor="ccffcc" | 45 || June 4 || Reds || 2–1 || Reuss (5–4) || Norman || Hernandez (1) || 13,754 || 25–20 |- bgcolor="ccffcc" | 46 || June 6 || Giants || 7–2 || Kison (6–1) || Barr || — || 11,923 || 26–20 |- bgcolor="ccffcc" | 47 || June 7 || Giants || 7–6 || Hernandez (2–2) || Toms || Giusti (5) || 8,668 || 27–20 |- bgcolor="ffbbbb" | 48 || June 8 || Giants || 1–3 || Halicki || Candelaria (0–1) || — || — || 27–21 |- bgcolor="ffbbbb" | 49 || June 8 || Giants || 2–4 || Lavelle || Demery (2–1) || Moffitt || 24,128 || 27–22 |- bgcolor="ccffcc" | 50 || June 9 || @ Reds || 9–2 || Reuss (6–4) || Norman || — || 22,555 || 28–22 |- bgcolor="ccffcc" | 51 || June 10 || @ Reds || 9–5 || McDowell (2–1) || Darcy || Hernandez (2) || 19,107 || 29–22 |- bgcolor="ffbbbb" | 52 || June 11 || @ Astros || 1–5 || Dierker || Kison (6–2) || — || 10,125 || 29–23 |- bgcolor="ccffcc" | 53 || June 12 || @ Astros || 4–2 || Ellis (3–3) || Roberts || Demery (2) || 10,802 || 30–23 |- bgcolor="ccffcc" | 54 || June 13 || @ Braves || 8–3 || Rooker (4–3) || Odom || — || 8,998 || 31–23 |- bgcolor="ccffcc" | 55 || June 14 || @ Braves || 2–1 || Reuss (7–4) || Thompson || Giusti (6) || 29,308 || 32–23 |- bgcolor="ccffcc" | 56 || June 15 || @ Braves || 8–6 || Demery (3–1) || Sosa || — || 8,352 || 33–23 |- bgcolor="ccffcc" | 57 || June 16 || Cardinals || 10–4 || Kison (7–2) || Bryant || — || 13,003 || 34–23 |- bgcolor="ffbbbb" | 58 || June 17 || Cardinals || 4–7 || McGlothen || Ellis (3–4) || Garman || 15,898 || 34–24 |- bgcolor="ccffcc" | 59 || June 18 || Cardinals || 9–3 || Rooker (5–3) || Reed || — || 22,345 || 35–24 |- bgcolor="ccffcc" | 60 || June 19 || Cardinals || 5–0 || Reuss (8–4) || Curtis || — || 8,198 || 36–24 |- bgcolor="ccffcc" | 61 || June 20 || @ Mets || 5–1 || Candelaria (1–1) || Hall || — || 47,867 || 37–24 |- bgcolor="ccffcc" | 62 || June 21 || @ Mets || 7–3 || Hernandez (3–2) || Parker || — || 31,610 || 38–24 |- bgcolor="ccffcc" | 63 || June 22 || @ Mets || 2–0 || Ellis (4–4) || Tate || — || 34,287 || 39–24 |- bgcolor="ffbbbb" | 64 || June 23 || @ Phillies || 5–6 || Hilgendorf || Demery (3–2) || Garber || 34,759 || 39–25 |- bgcolor="ffbbbb" | 65 || June 24 || @ Phillies || 3–6 || Christenson || Reuss (8–5) || McGraw || — || 39–26 |- bgcolor="ffbbbb" | 66 || June 24 || @ Phillies || 1–8 || Underwood || Kison (7–3) || — || 50,463 || 39–27 |- bgcolor="ffbbbb" | 67 || June 25 || @ Phillies || 6–7 (13) || Schueler || Giusti (2–3) || — || 34,171 || 39–28 |- bgcolor="ccffcc" | 68 || June 26 || Cubs || 5–2 || Candelaria (2–1) || Frailing || — || 10,394 || 40–28 |- bgcolor="ccffcc" | 69 || June 27 || Cubs || 5–1 || Ellis (5–4) || Zahn || — || — || 41–28 |- bgcolor="ccffcc" | 70 || June 27 || Cubs || 5–3 || Hernandez (4–2) || Knowles || Giusti (7) || 34,972 || 42–28 |- bgcolor="ffbbbb" | 71 || June 28 || Cubs || 0–1 || Bonham || Rooker (5–4) || — || 16,477 || 42–29 |- bgcolor="ccffcc" | 72 || June 29 || Cubs || 4–3 || Giusti (3–3) || Reuschel || — || — || 43–29 |- bgcolor="ccffcc" | 73 || June 29 || Cubs || 7–0 || Reuss (9–5) || Dettore || — || 37,145 || 44–29 |- bgcolor="ccffcc" | 74 || June 30 || @ Expos || 5–3 || Demery (4–2) || Blair || Tekulve (1) || 13,134 || 45–29

|- bgcolor="ccffcc" | 75 || July 1 || @ Expos || 10–4 || Candelaria (3–1) || Fryman || — || 15,132 || 46–29 |- bgcolor="ccffcc" | 76 || July 3 || @ Expos || 5–1 || Ellis (6–4) || Rogers || — || 10,116 || 47–29 |- bgcolor="ffbbbb" | 77 || July 4 || @ Cubs || 1–6 || Stone || Kison (7–4) || — || — || 47–30 |- bgcolor="ffbbbb" | 78 || July 4 || @ Cubs || 1–2 (11) || Knowles || Reuss (9–6) || — || 30,355 || 47–31 |- bgcolor="ccffcc" | 79 || July 5 || @ Cubs || 5–4 || Rooker (6–4) || Burris || Hernandez (3) || 22,393 || 48–31 |- bgcolor="ccffcc" | 80 || July 6 || @ Cubs || 18–12 || Hernandez (5–2) || Frailing || — || 28,023 || 49–31 |- bgcolor="ccffcc" | 81 || July 7 || @ Cubs || 5–0 || Brett (5–2) || Reuschel || Giusti (8) || 16,540 || 50–31 |- bgcolor="ffbbbb" | 82 || July 8 || Dodgers || 0–3 || Sutton || Ellis (6–5) || Marshall || 29,376 || 50–32 |- bgcolor="ccffcc" | 83 || July 9 || Dodgers || 3–2 || Kison (8–4) || Messersmith || Giusti (9) || 22,163 || 51–32 |- bgcolor="ccffcc" | 84 || July 10 || Dodgers || 4–1 || Reuss (10–6) || Hooton || Giusti (10) || 18,521 || 52–32 |- bgcolor="ccffcc" | 85 || July 11 || Padres || 6–2 || Rooker (7–4) || Folkers || Giusti (11) || — || 53–32 |- bgcolor="ccffcc" | 86 || July 11 || Padres || 5–0 || Candelaria (4–1) || McIntosh || — || 31,435 || 54–32 |- bgcolor="ccffcc" | 87 || July 12 || Padres || 6–4 || Hernandez (6–2) || Jones || Demery (3) || 21,877 || 55–32 |- bgcolor="ffbbbb" | 88 || July 13 || Padres || 5–7 || Strom || Ellis (6–6) || Spillner || 20,113 || 55–33 |- bgcolor="ccffcc" | 89 || July 17 || @ Dodgers || 5–2 || Kison (9–4) || Messersmith || Giusti (12) || 32,806 || 56–33 |- bgcolor="ffbbbb" | 90 || July 18 || @ Dodgers || 3–4 || Marshall || Demery (4–3) || — || 52,506 || 56–34 |- bgcolor="ccffcc" | 91 || July 19 || @ Dodgers || 5–3 || Giusti (4–3) || Marshall || — || 51,591 || 57–34 |- bgcolor="ffbbbb" | 92 || July 20 || @ Giants || 1–2 || Halicki || Rooker (7–5) || — || — || 57–35 |- bgcolor="ccffcc" | 93 || July 20 || @ Giants || 7–1 || Brett (6–2) || Caldwell || — || 14,723 || 58–35 |- bgcolor="ffbbbb" | 94 || July 21 || @ Giants || 2–7 || Barr || Candelaria (4–2) || — || 3,417 || 58–36 |- bgcolor="ffbbbb" | 95 || July 22 || @ Padres || 0–1 || Jones || Kison (9–5) || — || 14,437 || 58–37 |- bgcolor="ccffcc" | 96 || July 23 || @ Padres || 8–1 || Ellis (7–6) || Freisleben || — || 14,547 || 59–37 |- bgcolor="ccffcc" | 97 || July 25 || Expos || 6–1 || Reuss (11–6) || DeMola || — || 20,124 || 60–37 |- bgcolor="ffbbbb" | 98 || July 26 || Expos || 2–5 || Rogers || Rooker (7–6) || — || 4,394 || 60–38 |- bgcolor="ccffcc" | 99 || July 27 || Expos || 4–1 || Brett (7–2) || Scherman || Demery (4) || — || 61–38 |- bgcolor="ccffcc" | 100 || July 27 || Expos || 5–3 || Giusti (5–3) || Warthen || — || 27,961 || 62–38 |- bgcolor="ffbbbb" | 101 || July 28 || Phillies || 2–5 || Christenson || Kison (9–6) || — || 30,221 || 62–39 |- bgcolor="ffbbbb" | 102 || July 29 || Phillies || 1–5 || Underwood || Ellis (7–7) || — || 33,340 || 62–40 |- bgcolor="ccffcc" | 103 || July 30 || Phillies || 8–1 || Reuss (12–6) || Carlton || — || 43,260 || 63–40 |- bgcolor="ffbbbb"