The incident occurred just before 3:30 p.m. in an area known as The Cove, near Tillamook Head, according to Jon Rahl, a spokesman for the city. The victim, who has not been named, was bitten in the leg, but suffered non-life threatening injuries, KOIN-TV reported.
The surfer was treated by Seaside Fire and local medics after he was carried to the parking lot. An off-duty Seaside lifeguard had applied a field tourniquet to the man's leg to help slow the bleeding as help arrived, officials said.
The victim was taken to a local hospital and treated for his injuries.
Rahl said in a statement that “The fact that there were additional people on scene helped move this along pretty quickly.”
Oregon has recorded a total of 28 shark attacks since 1837, according to the Florida Museum of Natural History, which tracks shark attacks worldwide.