The men's 100 metre butterfly event at the 2009 World Aquatics Championships took place between 31 July – 1 August at the Foro Italico. Both the heats and semifinals were held on 31 July with the heats being held in the morning session and the semifinals being held in the evening session. The final was held on 1 August.

Records Prior to this competition, the existing world and competition records were as follows: World record 50.22 Indianapolis, United States 9 July 2009 Championship record 50.40 Montreal, Canada 30 July 2005 The following records were established during the competition:

DateRoundNameNationalityTimeRecord 31 July Semifinal 2 Milorad Čavić Serbia 50.01 WR 1 August Final Michael Phelps 49.82 WR

Results

Heats Rank Name Nationality Time Heat Lane Notes 1 Milorad Čavić 50.56 15 4 NR 2 Tyler McGill 50.90 15 5 2 Michael Phelps 50.90 17 4 4 Andrew Lauterstein 50.93 16 5 5 Albert Subirats 51.02 17 7 SA 6 Gabriel Mangabeira 51.11 17 3 NR 7 Ivan Lenđer 51.22 15 7 7 Benjamin Starke 51.22 16 6 NR 9 Takuro Fujii 51.24 15 3 AS 10 Rafael Muñoz 51.40 16 4 11 Peter Mankoč 51.49 16 3 12 Yevgeny Korotyshkin 51.51 15 6 NR 13 Nikolay Skvortsov 51.58 15 1 14 Michael Rock 51.65 16 8 NR 15 Corney Swanepoel 51.71 17 2 16 Jason Dunford 51.76 17 5 17 Ryan Pini 51.81 16 2 17 Clement Lefert 51.81 17 6 19 Joeri Verlinden 51.97 14 4 NR 19 Helge Meeuw 51.97 15 9 21 Adam Pine 51.98 17 0 22 Michal Rubáček 51.99 12 2 23 Robin van Aggele 52.04 14 3 24 Pavel Sankovich 52.05 13 5 25 Zhou Jiawei 52.08 14 2 25 Lyndon Ferns 52.08 15 8 27 Mario Todorović 52.09 14 5 28 Moss Burmester 52.13 17 8 29 Kaio de Almeida 52.14 15 2 30 Denys Dubrov 52.21 13 9 31 Simon Sjödin 52.27 13 8 31 Lars Frölander 52.27 16 9 33 Masayuki Kishida 52.28 17 1 34 Jakob Andkjær 52.34 15 0 35 Douglas Lennox-Silva 52.39 12 4 NR 36 Pablo Marmolejo 52.48 12 8 NR 37 Jeong Doohee 52.50 12 3 38 Mattia Nalesso 52.55 14 7 38 Ian Hulme 52.55 17 9 40 Joe Bartoch 52.60 14 9 41 Alex Villaecija 52.61 16 7 42 Sergiy Breus 52.63 13 0 43 Shi Feng 52.64 16 1 44 Alon Mandel 52.68 13 1 NR 45 Marcin Babuchowski 52.75 14 8 46 Vytautas Janušaitis 52.76 11 5 47 Stefanos Dimitriadis 52.89 13 3 48 Pavels Kondrahins 52.92 10 4 48 Evgeny Lazuka 52.92 12 7 50 Diogo Carvalho 52.94 14 6 51 Simão Morgado 52.98 13 4 52 Jan Šefl 52.99 13 7 53 Darian Townsend 53.04 16 0 54 Marcin Tarczyński 53.06 14 1 55 Shaune Fraser 53.07 11 2 56 Octavio Alesi 53.12 12 1 56 François Heersbrandt 53.12 14 0 58 Emil Dall-Nielsen 53.20 13 6 58 Rimvydas Salcius 53.20 13 2 60 Gustavo Daniel Paschetta 53.30 11 7 61 Daniel Bego 53.33 11 1 62 Andrejs Dūda 53.41 12 0 63 Elvis Burrows 53.51 11 9 NR 64 Alexandru Felix Maestru 53.61 11 3 65 Damien Courtois 53.91 10 3 66 Bernhard Wolf 53.98 11 4 67 Rustam Khudiyev 54.01 10 6 67 Alexandre Bakhtiarov 54.01 10 1 69 Mathieu Fonteyn 54.02 12 9 70 Emmanuel Crescimbeni 54.08 8 3 NR 71 Nadav Kochavi 54.20 9 4 72 Hsu Chi-Chieh 54.34 10 7 73 Stanislav Kuzmin 54.41 10 0 74 Romāns Miloslavskis 54.42 8 9 75 Israel Duran 54.52 10 8 76 Serkan Atasay 54.66 10 2 77 Sten Indrikson 54.73 9 3 78 Martin Liivamägi 54.74 9 6 79 Yu Jeongnam 54.78 10 5 80 Tan Xue Wei Nicholas 54.84 9 8 81 Grant Beahan 54.89 8 4 NR 82 Goksu Bicer 54.93 9 5 83 Bader Almuhana 55.11 9 2 NR 84 Andres Jose Gonzalez 55.23 10 9 85 Virdhawal Khade 55.28 11 6 86 Rehan Poncha 55.29 7 3 87 Nguyen Vo Thai 55.37 7 5 88 Branden Whitehurst Virgin Islands 55.46 5 1 NR 89 Sergey Pankov 55.48 8 6 90 Carlos Viveros Madariaga 55.55 9 1 91 Norbert Trudman 55.90 11 0 92 Glenn Victor Sutanto 55.92 11 8 93 Favio Persano 55.93 8 2 94 Taki Mrabet 55.94 9 7 95 Hajder Ensar 56.17 7 2 96 James Walsh 56.38 6 4 97 Conor Leaney 56.39 9 9 98 Brad Hamilton 56.56 6 0 NR 99 Endi Babi 56.58 5 5 100 Wong Wing Cheung Victor 56.65 9 0 101 Phillipe Mailliard Rodriguez 56.68 6 3 102 Bruno Miguel Esquen Blas 56.80 8 8 103 Emin Noshadi 56.84 6 1 104 Pedro Pinotes 56.92 5 0 105 Obaid Al-Jasmi 56.96 7 7 105 Joao Matias 56.96 7 0 107 Alexander Ray 56.97 4 5 108 Teymur Guliyev 57.06 8 7 109 Sim Ri Jin Nicholas 57.10 7 6 110 Serghei Golban 57.14 5 2 111 Roy Felipe Barahona Fuentes 57.15 7 4 112 Radhames Kalaf 57.33 5 7 113 Yellow Yeiyah 57.37 4 3 114 Javier Hernandez Maradiaga 57.41 8 5 115 Marcelino Richaards 57.44 6 2 116 Miguel Navarro 57.48 5 8 117 Fernando Castellanos 57.75 5 9 118 Nather Ahmed Alhamoud 57.82 6 6 119 Joel Romeu Lemarchand 57.97 7 9 120 Kareem Ennab 57.99 4 6 121 Serghei Falcas 58.12 5 6 122 Byron Briedenhann 58.28 4 2 123 Luke Hall 58.55 5 4 124 Ryan Nelthropp 58.65 4 7 125 Aleksei Klimenko 58.69 8 1 126 Alejandro Madde Madde 58.72 4 1 127 Abbas Raad 58.77 6 9 128 Ali Al Kaabi 58.81 4 4 129 Pietro Camilloni 58.99 5 3 130 Nasir Ali 59.12 4 9 131 Chong Cheok Kuan 59.22 6 8 132 Rashid Iunusov 59.40 7 1 133 Timothy Ferris 59.49 6 7 134 Andrey Molchanov 59.68 2 7 135 Fernando Medrano 59.80 3 4 136 Neil Agius 59.86 3 6 137 Jon Pepaj 1:00.05 7 8 138 Niall Christopher Roberts 1:00.53 4 8 139 Heimanu Sichan 1:00.55 3 3 140 Colin Bensadon 1:00.56 3 7 141 Jean Marie Emmanuel Froge 1:00.86 3 8 142 Benjamin Gabbard 1:00.87 3 9 143 Moh'D Aqelah 1:00.97 4 0 144 Papa Madiop Ndong 1:01.03 3 2 145 Paul Elaisa 1:02.40 2 1 146 Gerusio Matonse 1:03.36 3 0 147 Anthony Clark 1:03.37 2 6 148 Milimo Mweetwa 1:03.86 2 2 149 Jean Hugues Gregoire 1:03.89 2 5 150 Peter Popahun Pokawin 1:04.62 2 8 151 Narantsog Tsogjargal 1:05.01 2 4 152 Sergey Pevnev 1:05.15 3 1 153 Ali Mohamed Raaidh 1:10.10 2 9 154 Mohamed Mujahid 1:10.32 1 4 155 Johnny Rivera 1:10.49 1 5 156 Ingabire-Ahishakiye Gael 1:19.25 2 0 – Duje Draganja DNS 1 3 – Achelhi Bilal DNS 3 5 – Rami Anis DNS 6 5 – Édgar Crespo DNS 8 0 – Omar Pinzón DNS 12 5 – Stefan Hirniak DNS 12 6 – Jean-Luc Augier DSQ 2 3

Semifinals Rank Name Nationality Time Heat Lane Notes 1 Milorad Čavić 50.01 2 4 WR 2 Michael Phelps 50.48 1 4 3 Rafael Muñoz 50.59 1 2 4 Albert Subirats 50.65 2 3 SA 5 Jason Dunford 50.78 1 8 AF 6 Gabriel Mangabeira 51.02 1 3 NR 7 Andrew Lauterstein 51.03 1 5 8 Tyler McGill 51.07 2 5 9 Yevgeny Korotyshkin 51.26 1 7 NR 10 Benjamin Starke 51.31 1 6 11 Takuro Fujii 51.32 2 2 11 Ivan Lenđer 51.32 2 6 13 Michael Rock 51.41 1 1 NR 14 Nikolay Skvortsov 51.50 2 1 15 Peter Mankoč 51.54 2 7 16 Corney Swanepoel 51.79 2 8

Final Rank Lane Name Nationality Time Notes 5 Michael Phelps 49.82 WR 4 Milorad Čavić 49.95 ER 3 Rafael Muñoz 50.41 NR 4 6 Albert Subirats 50.79 5 1 Andrew Lauterstein 50.85 OC 6 2 Jason Dunford 51.07 7 8 Tyler McGill 51.42 8 7 Gabriel Mangabeira 51.74

References Worlds 2009 results: Men's 100m butterfly Heats, from OmegaTiming.com (official timer of the 2009 Worlds); retrieved 2009-08-06. Worlds 2009 results: Men's 100m butterfly Semifinals, from OmegaTiming.com (official timer of the 2009 Worlds); retrieved 2009-08-06. Worlds 2009 results: Men's 100m butterfly Finals, from OmegaTiming.com (official timer of the 2009 Worlds); retrieved 2009-08-06.