Liu, one of the favourites for the gold medal, injured his right leg and limped off the track.
Great Britain's Andy Turner won that heat in 13.42, while the other heats saw wins for Sergey Shubenkov of Russia, the USA's Jason Richardson and Aries Merritt, as well as Orlando Ortega and Dayron Robles of Cuba.
Merritt goes into tomorrow's semi-finals as the fastest qualifier, with a time of 13.07.
Merritt, world number one, said: 'It's just a tragedy for that to happen to one of the best hurdlers of all time.
'I hope he's okay. It's a shame that had to happen to Liu.'
Liu also had his hopes smashed at Beiging 2008, when injury denied him the chance to defend his 110m Hurdle title on home soil.
The disappointment echoed that of four years ago, when Liu stunned the crowd by walking off the start line, unable to run because of an Achilles problem.
'I feel really sorry about this situation,' said Feng Shuyong, the Head Coach of the Chinese Athletics team. 'We think it was like four years ago, the same thing happened again.
'I feel really sad because he has worked very hard to get back to the level he was at before as champion.
'What I saw on the big screen was that he could not take off. I think the problem just happened with that. At the moment of take off the tendon would bear very, very big pressure. He could not make the movement.
'You see him running well in certain competitions, but not many people know how he achieves this level. That's why I appreciate a lot his hard work and his very strong willpower.
'Seeing him hopping to the line shows the true spirit of the Olympic Games, he was still determined to go to the line.'