Cycling wheelchairs have been developed for the rehabilitation of those with walking difficulties. They are mainly designed for indoor use and are usually difficult to use out-doors because they got easily stacked. We proposed a system with a power assist function to enable safe outdoor use of cycling wheelchairs. In this paper, we described the disturbance compensation control to counter the running resistance during running of the cycling wheelchair, and summarize the evaluation results on pedaling torque, running time, and running path by an experiment.