Provided is a bipedal walking robot which includes a linear actuator, which connects a crus link and a foot of each leg away from an ankle joint, for driving the foot to rock around the ankle joint with respect to the crus link according to a telescopic motion thereof. The robot is capable of applying a desired moment to the foot for walking on stairs without increasing the linear actuator in size. The linear actuator is disposed in such a way that a telescopic force therefrom acts on a line inclined backward with respect to a connection line connecting a knee joint and the ankle joint. Preferably, a connection portion, which is connected to the crus link, of the linear actuator is disposed backward from the connection line, and a connection portion, which is connected to the foot, of the linear actuator is disposed forward from the connection line.