A load control system for a work vehicle including set rotation speed detection means for detecting a set rotation speed of an engine of the work vehicle, actual rotation speed detection means that senses an actual rotation speed of the engine, a continuously variable speed change device that receives power from the engine of the work vehicle, speed change position detecting means for detecting a speed change operating position of the continuously variable speed change device, operating means for speed-shifting the continuously variable speed change device, and control means for controlling the operation of the operating means.