[Purposes] In order to improve the control accuracy and fast response property of manipulator path. [Methods] Feature points are used to improve the geometric algorithm of inverse kinematics solution of serial six-axis manipulator. [Findings] The end pose of the manipulator could be represented by three feature points, and the first five joints are divided into three groups: joint 1, joint 2 and joint 3, joint 4 and joint 5. The angles of the first five joints are determined by two feature points. And two link poses could be gotten from each group, which could be combined into eight poses of the first five links. Then the solution of joint 6 is determined according to the pose of the first five links and another feature point. Comparing with the target terminal pose, the terminal pose determined by the angle value is calculated by the inverse solution had no theoretical error, which is consistent with the target terminal pose. [Conclusions] The improved geometric inverse solution algorithm of serial six-axis manipulator is simple, correct and feasible.