A British tourist drowned while trying to rescue his two sons who were caught in a rip at a southern NSW beach.

The 44-year-old was with family at a beach south of Ulladulla when his sons encountered trouble about noon on Friday, police said.

The man went to help them but was caught in danger himself, Fairfax reports.

Fellow beach-goers brought the boys to shore.

The British man was found floating face down.

People at the beach started CPR on the man and paramedics continued attempts but they could not revive him.

He was pronounced dead upon arrival at Milton Ulladulla Hospital.