The invention relates to a method and system for controlling the gait of a robot. The method includes determining whether a robot is walking and a direction in which the robot is walking; measuring an amount of time taken for a sole of a foot of the robot to step on the ground; calculating an imaginary reaction force applied to the sole using a trigonometric function having, as a period, the measured amount of time taken for the sole to step on the ground; and applying the calculated imaginary reaction force to a Jacobian transposed matrix and converting the imaginary reaction force into a drive torque for a lower extremity joint of the robot.