Penderecki was the youngest of three siblings; his sister, Barbara, was married to a mining engineer, and his older brother, Janusz, was studying law and medicine at the time of his birth.
Penderecki foi o máis pequeno de sete irmáns; súa irmá, Barbara, que casou cun enxeñeiro de minas, e seu irmán maior, Janusz, estudou dereito e medicina na época na que el naceu.