Quintus Petronius Didius Severus was a Roman who lived in the 2nd century. Severus' family was one of the most prominent and significant families in Midolanensis or Mediolanum (modern Milan, Italy).

Severus was of the gens Petronia. His father was Quintus Petronius Severus, born c. 70 AD, was a distinguished General and had a sister named Petronia Vara, born c. 75 AD. His