The invention provides a pole-changing positioning mechanism and a pole-changing positioning method for a multi-pole deep lunar soil sampler. The pole-changing positioning mechanism comprises a clamping mechanism and a pole-changing mechanism, wherein the clamping mechanism comprises a support mechanism at the lower end, a guide mechanism at the upper end and a central rotating shaft. The support mechanism at the lower end comprises a cylindrical clamp, a tension spring, a rotating shaft of the cylindrical clamp, a clamp rotating disc, a bolt A and a nut A; the guide mechanism at the upper end comprises a guide handle, a screw A, a guide rotating disc, a bolt B and a nut B; and the pole-changing mechanism comprises a positioning sliding block A, a positioning sliding block B, the rotating shaft of a lever frame, a pivot bracket, a return spring, the lever frame, a screw B, a pivot rotating shaft and a gear case. The pole-changing positioning mechanism has simple structure and low energy consumption, and can simplify the control process; simultaneously, the pole-changing positioning mechanism can solve the motion interference problem during pole-changing positioning, lead a drill rod to realize complete drilling down and achieve the desired sampling depth.