The anti-ship missile fired from the Sea King helicopter into the open sea successfully hit its target, Dawn newspaper quoted the spokesperson as saying.
Chief of the Naval Staff Admiral Muhammad Zakaullah witnessed the missile firing demonstration.
Mr Zakaullah said the successful firing demonstration was a testament to Pakistan Navy's war preparedness and professional capabilities.
The naval chief also visited the fleet units stationed in the sea and witnessed the exercises being carried out by the naval fleet.
Earlier in March, the navy had conducted a successful test of a land-based, anti-ship missile. The trial was conducted from the coastal region and the missile secured a hit on a target placed at sea, the report said.
The Pakistan Navy in May received the seven Westland Sea King multi-role helicopters it had ordered from the United Kingdom UK in 2016, it said.