The invention discloses an intelligent control method, device and system for a multi-joint mechanical arm. The intelligent control method for the multi-joint mechanical arm includes: receiving a velocity vector of a tail end of the mechanical arm, input by a manipulation device; performing trajectory prediction on each knuckle arm of the multi-joint mechanical arm on the basis of the velocity vector of the tail end of the mechanical arm; determining an optimal planning solution on the basis of the motion restraint and trajectory prediction result of the multi-joint mechanical arm; according to the optimal planning solution, determining the oil cylinder driving quantity of each knuckle arm; according to a proportional feature of the oil cylinder driving quantity and an execution mechanism, determining a driving current used for driving rotation of a multi-joint arm rest and a rotating tower. The intelligent control method, device and system for the multi-joint mechanical arm is capable of further improving the control precision of the multi-joint mechanical arm and well ensuring the stable motion of the arm rest and reducing the complexity of the manipulation.