In a walking assistance device that includes a pelvis support member adapted to be worn around a hip of a wearer and at least one actuator having a base end mounted on the pelvis support member and a free end engaging a thigh of the wearer, the pelvis support member comprises a substantially U-shaped base portion having a relatively high rigidity and adapted to be worn around the hip of the wearer and a pair of flaps having a relatively high resilient flexibility and extending from either end of the base portion toward each other; free ends of the flaps defining a gap smaller than a width of the hip of the wearer. Therefore, the wearer can bend the flaps outward so as to define a gap wide enough to pass the hip of the wearer, and once the wearer is fit into the pelvis support member, the flaps are allowed to return to their original shape owing to their resiliency, and engage the front side part of the hip of the wearer. The base portion, on the other hand, may be given with an adequate rigidity to support the actuator without any problem.