Most of hemiplegic subjects need foot drop correction in order to decrease the risk of falling during walking. Since compensatory movements such as circumduction and steppage gait are considered to be developed to achieve foot clearance in the swing phase, such movements might be improved if enough ankle dorsiflexion is developed in the swing phase. In this paper, hip joint and ankle joint angles of a hemiplegic subject were measured during walking with inertial sensors, when FES foot drop correction was applied. As the ankle dorsiflexion angle decreased by muscle fatigue, hip flexion angle begun to increase earlier and timings of the heel off and the toe off were detected earlier, which were similar to gait movement of the subject without FES foot drop correction. These changes were considered to be a preparatory movement for achieving foot clearance by increasing hip flexion. This result suggested that the compensatory movements by the hip joint could be improved by FES foot drop correction.