Chief Deputy Stacy Brown said the body was recovered Friday night.
The southwest Washington river's water level dropped sufficiently in the last day to allow the boy's body to become visible in a logjam.
Brown says the body will be turned over to the county coroner's office. The boy was not identified by name.
The boy was camping with his family along the river about 10 miles from Randle. He was riding his miniature motorcycle and Brown says it appears he just got too close to the river bank.
Brown said the boy's 32-year-old father ran to the water and jumped in after his son but was unable to rescue him.