There are fears that 78-year-old Yik Sua Hong was swept off the rocks while fishing at Blairgowrie on Sunday.

Mr Hong left his Wantirna home in Melbourne's east to go fishing at 9am on Sunday. The experienced rock fisherman told his wife he would be home between 6pm and 7pm, but he never returned.

His wife alerted their adult son, who went to the beach to look for his father.

He found his father's car locked in the beach carpark.

"Our fear is that he may have entered the water while fishing, but we haven't found any signs of clothing or fishing gear to actually confirm that," Acting Senior Sergeant Kirby Tonkin told Channel Nine on Monday morning.

"He knows this area quite well, he comes down here often. So it's unlikely that he's lost in the dunes or he doesn't know where he is.

"He does know the dangers of rock fishing, he's been doing it most of his life. Unfortunately he doesn't wear a life jacket."

The weather was sunny with a top of 28 degrees in Melbourne on Sunday, until a late cool change blew in. ???But the waters off the sandy beaches at Blairgowrie are known for wild swells and considered to be suitable for only strong swimmers and surfers.

Police began searching for Mr Hong about 10pm on Sunday, but were forced to stop at 1am on Monday due to bad weather.

The search resumed at 6am.

Police are using a helicopter to search the area. SES crews are also at the scene.

Police are appealing to anyone who might have seen Mr Hong fishing on Sunday and can shed light on what he was wearing to call Crime Stoppers on 1800 333 000.