Roche Harbor Seaplane Base is a public-use seaplane base located adjacent to Roche Harbor, on San Juan Island in San Juan County, Washington, United States. It is owned by the Roche Harbor Resort.
Roche Harbor Seaplane Base has two seaplane landing areas: NE/SW is 5,000 by 1,000 feet (1,524 x 305 m) and NW/SE is 2,500 by 500 feet (762 x 152 m). For the 12-month period ending May 31, 2009, the airport had 2,800 aircraft operations, an average of 233 per month: 57% air taxi and 43% general aviation.