It is a biped (two-footed) walking humanoid robot, which is provided with drive motors (11d, 11e, 18L, 18R-24L, 24R, 28L, 28R-33L, 33R, 35, 36) to pivotally move respective joint portions, and a motion control apparatus (40) to drive-control respective drive motors, and said motion control apparatus (40), together with a detector (45) to detect the robot's current posture and others, compares the robot's detected current posture and others with next motion command input from outside, and if next motion command is within the range of stability limit with respect to the robot's current posture and others, the complementary data with respect to intermediate motion from current posture till initial posture of next motion command and the motion data corresponding to next motion command are generated, each drive motor is drive-controlled based on said complementary and motion data, and thereby various motions are conducted smoothly and continually. It is preferably provided with a motion library (41a) storing time series data of basic motions as the elements of the robot's motions and posture data consisting of algorithm, reads out the corresponding posture data from said motion library, and generates complementary and motion data as the combined motion sequence.