The Grey-headed Flying-fox like other flying-foxes  locates food by sight and smell.  They roost in large colonies during the day and feed at night.

Blossoms and nectar of eucalypts and other native flowering plants form the majority of their diet.  They can often be seen feasting on people's ripening fruit in their backyard eg. bananas.

Mating occurs in early autumn.   A single young is born in October and is carried by the female for four to five weeks.   Young can fly when eight to ten weeks and are independent at three months of age.

Camps are located in the branches of large trees or mangroves in eastern and south-eastern Australia.