Pictured: Hero father who drowned trying to save four children from rip

A Victorian father has been hailed a hero after he lost his life trying to help four children swept away by a rip in the surf at Wollongong City Beach.

Shaun Oliver rushed into the water to help two older children, aged 10 and 12, who were caught in a rip after their dad was rescuing two other children who got into trouble during a Sunday afternoon swim.

A surfer reached the pair and got the the older boy closer to shore while an off-duty paramedic helped pull the 10-year-old boy to shore.

Mr Oliver, who helped the 12-year-old make his way to safety, was swept out to sea before being pulled from the water by police and given CPR.

A man has died trying to save children from drowning at a NSW beach. Photo: 7 News

He later died in hospital, leaving behind his "childhood sweetheart" and three young children.

In an emotional GoFundMe post, Mr Oliver's brother, Nathaneal, said he made the ultimate sacrfifice to protect those who could not do so for themselves.

“Shaun has sacrificed his future happiness and shared life with wife Carla and three beautiful children to do what none of us hope to do in this lifetime.. be tested,” Nathanael wrote.

“Sadly not long before their 10-year anniversary, Shaun was faced with an ultimatum. He chose to protect those who could not protect themselves.

“And he, and his family, have paid a heavy price.”

The 32-year-old was swept out to sea while trying to save two children from drowning. Photo: 7 News

Surf Life Saving NSW has warned beachgoers of the dangers of the surf.

"It might look picturesque and tame but there is quite a strong undercurrent and tow," a spokesman said.

"Inexperienced people need to heed the warnings and don't go into the water."