Police investigating the suspected murder of Sydney student Jamie Gao believe a body found off the coast of Cronulla this morning may be that of the 20-year-old, who has been missing for almost a week.

A former NSW detective has been charged with Mr Gao's murder, and officers attached to the Robbery and Serious Crime Squad are waiting to speak to disgraced former detective Roger Rogerson over the disappearance.

A body found off the Sydney coast near Cronulla. Credit:Lachlan Stevens

Sources close to the investigation have told Fairfax Media the discovery of the body "fits" with the events they allege happened around the time of the Mr Gao's disappearance.

NSW detectives are flying to Queensland on Monday to talk to Mr Rogerson.