Petrislav is ruler of Duklja (or Diokleia), the most powerful Serbian principality of the time, until his death in around 1000.

It is unknown when his reign started.

The only preserved medieval source that mentions Petrislav is the Chronicle of the Priest of Duklja.

Historians identify him with Peter of Diokleia whose seal was found in the 19th century, which makes Petrislav the earliest Duklja's ruler whose existence is confirmed by primary historical sources.