Samuel Wainer (December 19, 1910 – September 2, 1980) was a Brazilian journalist and author. Wainer was born into a Jewish family in the São Paulo district of Bom Retiro. He founded and directed the Diretrizes magazine and the Última Hora newspaper. He was married to Danuza Leão, Brazilian journalist and model, sister of Nara Leão. They had a son, Samuel Wainer Filho, who was also a journalist. He died in 1984 in a car accident with a camera operator. Wainer also had more two children: plastic artist Débora "Pinky" Wainer and film producer Bruno Wainer.
He was a reporter of Diários Associados in 1950, when he interviewed Getúlio Vargas, with whom he would later keep a close friendship. He also faced strong opposition from Carlos Lacerda and Assis Chateaubriand (owner of Diários Associados) during his career, specially when he founded his own newspaper, that would openly support Vargas presidency.
Wainer was the only Brazilian journalist present at the Nuremberg Trials.
He died in São Paulo, aged 69.