Patrocles the Historian was a Greek historian and military commander who served under the Seleucid kings Seleucus I Nicator and Antiochus I Soter during the late 4th and early 3rd centuries BCE. His career is known from later geographical works, which identify him as a trusted general and satrap of eastern regions, possibly including Media and areas near the Caspian Sea. His floruit is generally placed circa 312–261 BCE.

His only known work, On the Caspian Sea, is lost but survives in fragments cited by later authors like Strabo and Pliny the Elder. Patrocles is a significant, though fragmentary, source for the historical geography of the Hellenistic East. His influential report described the Caspian Sea as a gulf of the Northern Ocean, a view later corrected.

His accounts of Central Asian trade routes and peoples provided important data for later geographers like Eratosthenes and Strabo, linking the knowledge from Alexander's campaigns with Hellenistic scholarship.