Abe McGrath, a 35-year-old Byron Bay man, was surfing with friends at Main Beach early on Sunday morning.

About 6.30am, Mr McGrath's board was hit from underneath by a shark.

He told police the impact caused him to fly into the air before landing back in the water.

As the shark circled him, Mr McGrath grabbed half his board and swam back to shore, police said.

"Life could of (sic) been very different this morning," Mr McGrath's friend Bryce Cameron posted on Instagram.

"So stoked to still have our mate and not witness something far worse... So stoked to see him able to limp up the beach."

Mr Cameron described the shark as a "juvenile white pointer".

Mr McGrath's friends drove him to hospital in Ballina, where he was treated for lacerations to his hip before he was transferred to Lismore Base Hospital

A spokeswoman from Lismore Hospital said the man was in a "very stable condition".

He was being treated for a wound on his right hip area, she said.

Main and Bluff beaches were closed as a result of the attack.

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