Abstract: This paper discussed the existence of closed-form solution and solving approach on inverse kine- matics for manipulators with 4,5 and 6DOF, First,sufficient conditions on existence and general calculatingsteps of closed-form solution are addressed by discussing on kinematic parameters a_i and d_i and a_i On thisbase,a new approach,the Iterative-Analytical Mixed Method(IAMM),is presented.This method is easy togive out all possible solution. According to these theory and methods,a general C-language program is devel-oped to solve inverse kinematic problems. At the end of this paper. two illustrating examples are given out.