In the first incident, a man in his 50s died after trying to save a 12-year-old boy - believed to be his son - after the boy became caught in a rip near Teddy's Lookout at Lorne.

Paramedics were called about 12.30pm to find the boy on the shore and the man unconsious on the beach after he was picked up in a dinghy by surf lifesavers.

They were unable to revive him and he died at the scene, while the boy was taken to Lorne Hospital in a stable condition, having swallowed water and suffered shock, Ambulance Victoria spokesman John Mullin said.

About 2.30pm a man in his 30s drowned while snorkelling with friends at Rye.

The man was swimming in waters off Rye back beach but it is unclear how he came into difficulty.

Police say witnesses found him washed up against rocks and brought him to shore and tried to revive him but were unsuccessful.

And in a third incident, a man is missing in waters near Golden Beach at Sale, however a spokeswoman for Victoria Police said no further details were available.

Next of kin were being informed.

- Jill Stark and AAP