To provide a cab support structure for a construction machine restricting a rocking amount of a cab by impact or the like and capable of exhibiting shock-absorbing function without sacrificing riding comfort.

In the support structure of the cab 5 attached and supported by a damper mount 50 arranged at a vehicle body side, a stopper 10 of thin shape made of a shock-absorbing rubber material and having a projected contact surface central part is mounted near a support part by the damper mount 50 and at an appropriate position along a bottom surface edge of a floor frame 5a of the cab 5.