The invention provides an inverse kinematic solving method of manual operation and control of a multi-joint mechanical arm. The method is characterized in that the posture of each joint and the lengthof each driving rope in each time can be output after space trajectory functions are set; the mapping relation between an operation space and a joint space is solved by dichotomy in the numerical method while being settled; the transfer matrix of each joint coordinate system relative to a base coordinate system can be solved while the mapping relation between the joint space and a driving space is settled, and thus the length of each driving rope can be obtained. According to the method, the posture information of the mechanical arm and the length of the driving ropes in each time in the whole movement process can be obtained under the condition that the basic information of the mechanical arm are known.