Scottish Labour leader Jim Murphy has lost his East Renfrewshire seat to the SNP's Kirsten Oswald.
There were cheers from the crowd as the results were read out.
Murphy's once safe majority was eliminated as Oswald swept to victory with 23,564 votes to Labour's 19,295.
Murphy who had held the seat since 1997, said: "It has been a real pleasure to represent our area in Parliament for the past 18 years." He also congratulated Oswald on her win.
He said it was an "enormous" moment for the SNP, but appeared to be in good spirits as he declared the fightback for Labour in Scotland starts tomorrow.
"The fight goes on and our cause continues. I know hundreds of thousands of Scots still believe in the progressive policies the Labour party stands for, he said.
"The Scottish Labour party has been around for more than a century. A hundred years from tonight we will still be around.
"Scotland needs a strong Labour party and our fightback starts tomorrow morning."