The San Juan 24 is an American trailerable sailboat that was designed by Bruce Kirby as an International Offshore Rule Quarter Ton class racer.

[4] The design was built by the Clark Boat Company in Kent, Washington, United States, starting in 1973 but it is now out of production.

It has a masthead sloop rig, a raked stem, a raised reverse transom, an internally-mounted spade-type rudder controlled by a tiller and a fixed fin keel.

[6] In a 2010 review Steve Henkel wrote, "Don Clark, designer of the San Juan 21 Mk I and II ... and owner of the Clark Boat Company of Kent, WA, went to Bruce Kirby for a hot new racer to be designed to the IOR Quarter Ton Rule.

Best features: The boat has been a success (and, at least so far, is the most popular quarter tonner ever), with over a thousand sailing, Worst features: Although she is fast and weatherly going upwind, dead downwind in heavy air under spinnaker she can be a little squirrelly, possibly a result of her narrow underbody aft.