During the visit, Munir will meet key senior Iranian figures, the sources added.
It would be the second such trip to Tehran by Munir amid Pakistani mediation efforts to end the US-Israeli war of aggression which began on February 28.
Iran’s state-run IRNA news agency also confirmed that the Pakistani army chief had left for Tehran.
During his visit to Iran, Pakistani sources said, Munir will discuss Iran-US talks, regional peace and stability, and other “important issues.”
The sources did not disclose details about the duration of the visit.