The funnyman, who suffers from bipolar disorder, will takeover as the boss of Mind from Lord Melvyn Bragg, who has stepped down after 15 years in charge.
Announcing the news on Twitter.com, Fry writes, "Exciting news - I'm thrilled to reveal I will become the new president of the wonderful Mind charity."
The star, who has supported the organisation for several years, adds in a statement, "I am honoured and delighted to become the new president of Mind. This wonderful charity performs vital work to help anyone, like myself, who experiences a mental health problem.
"It is a privilege to follow in the footsteps of Lord Melvyn Bragg, and I can only hope to live up to the standard that he has set in his 15 successful years at the helm."