The chef, who helped the restaurant win a Michelin star in 2005, told BigHospitality he felt it was time to go it alone after nine years in the role and after building a successful TV career. He will remain at the restaurant until the end of 2012 before focusing on his next move.
He said: "When I opened Bohemia it was an exciting opportunity for me and really set a benchmark in Jersey. The job just grew and grew and my career diversified when I did media and TV stuff. I had two jobs really, building a brand and name for a restaurant as well as doing the day job and that can become tiring. After nine years I felt it was time to go out on my own."
Rankin, who moved to the Channel Islands 17 years ago, said he was looking at launching his own restaurant, but would not reveal any more details until early 2013 when he had fully cut his ties with Bohemia.
However, the chef did confirm he would be remaining in Jersey where his family continues to reside and where he has built up a strong supplier base over the years.
"I'm most proud of building a supply chain here," he said. "There was nothing set up when I arrived, but I think I've worked hard to craft a supply chain now with some wonderful producers and made it available to others. We have such a wonderful larder here, I wouldn't want to lose access to that."
Bohemia owner Lawrence Huggler credited Rankin with leading a 'renaissance' of fine-dining in Jersey and wished him well for his next venture.
"We wish Shaun every success in the future with his exciting new projects and we have very much enjoyed working together over nine fantastic years. I am looking forward to announcing shortly with whom and how we will be raising the bar once more for fine-dining in Jersey at Bohemia in 2013," he said.
Rankin makes regular appearances on Saturday Kitchen and appeared in the 2009 series of Great British Menu. The chef hopes to work on more produce-related TV shows in the future, like Island Feast, a six-part series that follows his visits to food producers on the Channel Islands, rather than in more chef competition programmes.
"Great British Menu was a great highlight for me and took me into a different area, but I won't be competing in it again, maybe judging, but definitely not to compete," he said."TV is a great marketing tool. It helped drive people to Jersey and get more bums on seats in the restaurant."