An important characteristic of people with partially impaired walking ability, such as incomplete paraplegics, is that they are able to generate voluntary motion of lower-limbs. Therefore, wearable robots for the incomplete paraplegic patients require a different assistance method compared to those of complete paraplegics. First, the wearable robot should be controlled to not resist wearer’s motion. Second, it should be able to generate assistive torque accurately when needed. In this paper, a wearable robot, called EROWA, for the incomplete paraplegic patients is introduced. EROWA utilizes compact rotary series elastic actuators (cRSEAs) and a control method called the zero impedance control to reduce the mechanical resistance. An assistive torque trajectory is proposed to assist gait in this paper. The proposed method is verified by simulation and experimental studies.