ZEUS was a particle detector that operated on the HERA (Hadron Elektron Ring Anlage) particle accelerator at DESY, Hamburg. It began running together with HERA in 1992 and was functional until HERA was decommissioned in June 2007. The scientific collaboration behind ZEUS consisted of about 400 physicists from 56 institutes in 17 countries.

Zeus ( ; , Zeús, ; Modern , Días ) was the sky and thunder god in ancient Greek religion, who ruled as king of the gods of Mount Olympus. His name is cognate with the first element of his Roman equivalent Jupiter.