Płaczek () is a Polish surname. It is derived from the noun płacz, "crying". Notable people with the surname Płaczek or Placzek include:
Abraham Placzek (1799–1884), Moravian rabbi Adrianna Płaczek (born 1993), Polish handball player Baruch Placzek (1834–1922), Moravian rabbi and writer George Placzek (1905–1955), Czech physicist Joyce Placzek (1901–1953), English writer under name of Jan Struther Marysia Placzek (born 1960), British neuroscientist Otto Placzek (1884–1968), German sculptor Siegfried Placzek (1866–1946), German neurologist and psychiatrist Grzegorz Płaczek (born 1978), Polish politician
See also Plaček, Czech surname of the same origin Placek Placzek transient, a concept in nuclear engineering