The pungent smell of the rotten durian fruit at an Australian university library has been mistaken for a gas leak, prompting an evacuation of the building.

Specialist crews wearing masks searched the Royal Melbourne Institute of Technology university campus library on Saturday, but all they found was rotting durian in a cupboard.

About 600 staff and students had cleared the building.

A Metropolitan Fire Brigade spokesman said the smell alarmed staff and students as it permeated the air-conditioning system.

Durian is a tropical fruit known for its strong smell. It is commonly banned from hotel rooms and public transport across Southeast Asia.