At the 2008 European Championships in Zagreb, Lambiel had a disappointing short program, falling on his triple Axel and managing only a triple toe loop-double loop combination; he placed 4th. He finished 2nd in the long program after landing a quadruple toe loop-double toe loop-double loop combination and earning 80 points in program components score for his Flamenco program, a very high score at that time. He won his second European silver medal, behind Czech Tomáš Verner.
At the 2008 World Championships in Gothenburg, Sweden, Lambiel fell on his triple Axel and put his hand down on a quadruple toe loop in the short program, leaving him in fifth place going into the free skate. In the free skate, he stepped out of his triple Axel attempt, put his hand down again on the quadruple toe loop in his combination, and then stepped out of his solo quadruple toe loop. He finished in fifth place overall.
Lambiel was scheduled to compete at Grand Prix events in Canada and France but withdrew from both events. He announced his retirement from competitive skating on 16 October 2008, citing an injury to the adductor muscle in one of his thighs. He said, "It's seven months that I've been going to see the best doctors. I still have the pain and it's really not possible to train like that. I didn't have the ability to reach my objectives." He performed in many shows in Switzerland, France, Italy, South Korea and Japan, as well as the Canadian Stars on Ice tour.
In a 2008 interview, Alexei Mishin called him an "outstanding artist and spins genius" and added that his retirement was an "immense loss". According to Mishin, Lambiel was "strangled by the modern figure skating regulations".