The body was found shortly after 5:30 p.m. near Placentia and Orangethorpe avenues.
Investigators said someone reported seeing the body in the water.
Crews with Anaheim Fire and Rescue recovered the body near the shoreline.
Police said they're now working to determine if this is related to a homicide or if the person died due to other circumstances.
They're also working to identify the person and are looking into how long the body was in the water.
Anyone with information is urged to contact authorities.