They were part of an experiment into how astronauts might deal with the very cramped conditions and prolonged isolation of a journey to Mars.
The four Russians, a German and a Frenchman seemed none the worse for wear after their "trip".
The capsule, without windows, had never left the ground during the 105 days.
It was designed to make them feel as isolated as they would be on a real trip to Mars, including very cramped accommodation and radio communication delayed by up to 20 minutes.
Just before coming out on Tuesday, the German member of the group admitted that he had completely lost all track of time.
However, 105 days is not nearly long enough to get to Mars and back.
So next year another group of volunteers will enter the same cramped capsule and be sealed inside for a daunting 520 days - nearly a year and a half.