The invention provides an initialization method for redundant manipulator motion planning, which comprises the following steps of: 1) starting a redundant manipulator controller, and adjusting the redundant manipulator to a limit position; 2) taking the limit position in the step 1) as an initial value of the initialization method, and setting a manipulator task execution position as an end value of the initialization method so as to transform a manipulator control problem into a corresponding quadratic planning problem; 3) solving the quadratic planning problem in the step 2) by utilizing a quadratic planning solver; and 4) using a result obtained in the step 3) for driving various joint motors to make the manipulator rotate from the limit position to the task execution position. The quadratic planning-based initialization method avoids the complicated process of measuring the angles of various joints in each task operation, and specifies an initial position of each task according to a task requirement.