The application of the constant speed cruise function on the electric bicycle can effectively improve the riding comfort and safety of electric bicycles. However, the existing constant speed cruise function of electric bicycles has a weak ability to adjust to different road conditions. In order to solve the above problem, this paper studied the cruise condition of electric bicycle, and proposed a speed control system based on the driver’s intention during electric bicycle cruising. Under the premise of ensuring safety, by setting the variable speed switch and the speed control threshold, the speed of the electric bicycle under cruising conditions was adjustable and the speed regulation process was smooth. The slope of the speed change was set to suppress the fluctuation of the bicycle speed during the cruise exit, so as to improve the comfort of riding the bicycle. The thresholds of rotational speed and torque fluctuations were set to judge unexpected situations during the cruising process of the bicycle to avoid secondary injuries. A hardware experiment platform was built to test the corresponding control strategy on bicycles. The experiment showed that the bicycle speed transited from 15 km/ h to 22 km/ h during the cruise, the bicycle power was not cut off during the whole process, and the bicycle speed had no obvious impact, which was in line with the expected goal. The results show that the designed control system is simple in operation and fast in response, which improves the safety, operability and comfort requirements of electric bicycles during cruising.