Man stable after Sydney apartment fall

A critically injured man who apparently fell from the window of a Sydney apartment is in a stable condition in hospital.

A passerby found the 39-year-old with a large cut across his stomach about 6.30pm on Tuesday on Shirley Road in Wollstonecraft.

He was treated at the scene for critical injuries and taken to Royal North Shore Hospital where his condition was said to be stable on Wednesday afternoon.

NSW Police say "initial investigation suggests the man may have fallen out of the window".

"The cause of the man's injuries are not being treated a suspicious," a spokesperson said in a statement.