Ágoston Valentiny (6 October 1888 – 21 August 1958) was a Hungarian politician and jurist, who served as Minister of Justice in the Interim National Government. He was born into a working-class family with six children. His father was a machine fitter and engineer. Valentiny finished his law studies in Kolozsvár. He joined the Hungarian Social Democratic Party on 1 January 1919. During the German occupation in 1944 he was interned. After the "Liberation" of Szeged he became mayor of the town. He was a member of the Interim National Assembly.