All the freed Indian prisoners had completed their jail terms and were handed over to Indian officials at Wagah border, a crossing between Pakistan's Lahore city and India's Amritsar, Xinhua reported.
All the prisoners were released from Pakistan's southern port city of Karachi Friday. While 329 prisoners were freed from Malir Jail, eight minors were released from the Youthful Offenders Home in the city's Landhi Jail.
Earlier Thursday, Pakistan's interior ministry announced to release 365 Indian prisoners, but later the number was reduced to 337 for unknown reasons.
The decision to release Indian prisoners comes at a time when both nuclear rival neighbours are facing a surge in tension due to cross-border firings that claimed lives on both sides.
Pakistan and India routinely arrest and jail each other's fishermen when they mistakenly violate the other's boundary. There are no maritime boundaries between the two countries and despite a series of talks no agreement has been finalised yet.
According to Pakistan's foreign ministry, there are at least 485 Pakistanis jailed in India, including 172 fishermen and 313 civilians.