Bednorz was born in Neuenkirchen, North Rhine-Westphalia, Germany to Anton and Elisabeth Bednorz.
In 1968, Bednorz started his studies in Mineralogy at the University of Münster.
In 1982, Bednorz was hired by IBM to work in their Zurich laboratories. There, he joined Karl Alexander Müller's ongoing research into superconductivity.
In 1983, Bednorz and Müller began a systematic study of the electrical properties of ceramics formed from transition metal oxides, and in 1986, they succeeded in inducing superconductivity in a barium lanthanum copper oxide (BaLaCuO, also known as LBCO); the oxide's critical temperature was 35 kelvins, a full 12 K higher than the previous record.
In 1987, Bednorz and Müller were jointly awarded the Nobel Prize in Physics.