A method of gear change control of a crawler construction machine equipped with a direct transmission. The machine is shifted up through a step of releasing right and left steering clutches, a step of increasing the number of revolutions of an engine, a step of releasing a main clutch, a step of releasing a dog clutch selecting the present gear, a step of connecting the main clutch, a step of detecting the number of revolutions of an output shaft of a transmission, a step of setting a target engine number of revolutions for accomplishing a synchronous engagement of the dog clutch for the next gear on the basis of the detected revolutions and the number of gears to be meshed in the transmission when the next gear is to be selected, a step of rotating the engine at the target engine number of revolutions, a step of meshing the dog clutch for the next gear, a step of connecting right and left steering clutches and a step of rotating the engine at the number of revolutions designated by a throttle lever. Thus the crawler construction machine can be shifted up smoothly without the necessity for stopping the machine.