The midfielder - formerly of Villa and Chelsea - joined The Cottagers in January on a six-month contract.
“I’m delighted to be tied down for another three years,” he told the club's official website. “The main objective was to come here in January and prove myself to get a contract. Now that’s been done I’m not going to sit on my laurels, I’m hopefully going to kick on."
He added: “I’d like to help in the progress of the Club and take it where the management and the owner want to take it. This has been a transitional year compared to the success the Club had last year. But I’ll be hoping to take each year as it comes and progress.”
Fulham's next fixture is a trip to Molineux on Saturday.