Steve Sansweet, who runs Rancho Obi-Wan museum in California, said more than 100 pieces had gone missing.
In a post online, he said many of the collectibles had already been resold.
Star Wars actors Mark Hamill and Peter Mayhew have both rallied behind the collector on Twitter.
Mr Sansweet, whose museum houses at least 350,000 artefacts linked to his beloved films, is a former head of fan relations at Lucasfilm, the studio that produced the Star Wars and Indiana Jones franchises.
Mr Hamill, who played Luke Skywalker in the film franchise, wrote: "Maybe publish a list of stolen items to protect potential victims from purchasing 'hot' merchandise. #TheFraudIsStrongInThisOne #SithHappens."
Chewbacca actor Mr Mayhew said: "This is despicable. Keep an eye out. Get the word out."
Mr Sansweet said the stolen items included vintage action figures, "many of them rare and important pieces".
He said they were taken surreptitiously over many months in late 2015 and 2016.
He urged fans with information on the missing items to email tips@ranchoobiwan.org.
Police have arrested another Star Wars collector, 45-year-old Carl Edward Cunningham, in connection with the crime. He has been charged with felony grand theft.
Mr Sansweet, who considered the fellow fan a longstanding friend, said he was "devastated".
The owner of the world's biggest Star Wars memorabilia collection has appealed to fans for help after items worth $200,000 (Â£154,900) were stolen from him.