Antoni Biernacki was born on 19 January 1901. During World War II, he lived in the village of Rozdziały (Mazowieckie voivodeship). He was sheltering a boy of Jewish origin. Antoni was sent to the Gross-Rossen camp, where he was murdered on 16 March 1944.

Antoni Biernacki was awarded the title of Righteous Among the Nations in 2005.