0709 GMT November 20, 2018
The world number one was beaten 6-7 (6-8), 6-3, 5-7, 7-6, (7-3) 6-1 in four hours and 34 minutes, BBC reported.
It was a repeat of last year's semifinal, which the Briton won before going on to lose the final to Novak Djokovic.
Former champion Wawrinka will play Rafael Nadal in French Open final later today after the Spaniard beat Dominic Thiem.
Nadal, who beat the Austrian 6-3, 6-4, 6-0, will become the first player in the open era to win 10 titles at one Grand Slam if he beats Wawrinka.
The 31-year-old Nadal is yet to drop a set in this year's tournament as he looks to secure his first Grand Slam since winning in Paris in 2014.
Fitness takes its toll on Murray
Wawrinka will get the chance to add a second Roland Garros title to his 2015 victory, and move ahead of Murray with four Grand Slam titles, after his shot-making won the day.
The Swiss hit 87 winners - 45 on the forehand side - as he finally overcame the determination and defensive skills of Murray.
Short on matches after a season interrupted by illness and injury, Murray got within four points of victory but ultimately ran out of gas as Wawrinka made him cover a punishing 4.5km over more than four hours.
"Physically I didn't feel my best at the end," said Murray. "It is more like I didn't have enough weight on my shot at the end to put him under any real pressure.
"A lot of the points he was dictating from the middle of the court, and I was retrieving and allowing him to pretty much hit the shots that he wants.
"And against a shot-maker, someone who hits the ball as big as him, that's obviously not ideal."
Nadal too strong for Thiem
Austria's Thiem, 23, is the only player to beat Nadal on clay this year and showed his serious promise by beating defending champion Novak Djokovic in the quarterfinal.
But, when faced with nine-time champion Nadal - who has only lost twice at Roland Garros - the challenge proved too much.
Thiem broke his opponent's serve in the first game of the match before Nadal repeated the trick in the following game.
The Austrian let four more break-point opportunities slip in a tight opening set but from that point Nadal dominated and he went on to complete victory in two hours and seven minutes.
"I was starting a little bit more nervous today than normal, but then I played well, I think," said Nadal.
"It's true that Dominic played with more mistakes than usual."
Asked about the prospect of a 10th title, he said: "I think I don't make more history, it's enough. Nine are more than good.
"Another thing is today is not the moment to think about that. It's the moment I have to be very happy."