NSW man shot in groin after opening door

A man has been shot in the groin after answering a knock on the door of his Sydney unit.

The 31-year-old man opened the door of his Hillsdale unit about 2pm on Sunday.

"Police have been told he was confronted by another man," according to a NSW Police statement.

"A shot was fired, and the man sustained an injury to his groin."

The wounded man was taken to St Vincent's Hospital in a stable condition.

The shooter is described as a slim Caucasian and about 170cm tall.

He wore a grey-coloured hooded jumper, and dark-coloured shorts.