Friction stir welding spindle head and friction stir welding device

The utility model provides a friction stir welding spindle head and a friction stir welding device, relates to the field of friction stir welding, and solves the technical problem that the performance of a welding seam is affected due to the fact that a key hole is formed in the welding seam when a stirring head for friction stir welding leaves the welding seam. The friction stir welding spindle head comprises a withdrawing driving mechanism, a spindle, a pull rod and a stirring needle, the spindle, the pull rod and the stirring needle are arranged on a static support, and at least part of the pull rod is located in an inner cavity of the spindle and can rotate along with the spindle; the stirring needle is connected to the lower end of the pull rod; the lower end of the main shaft is connected with a shaft shoulder, the withdrawing driving mechanism comprises a moving part, the moving part is rotationally connected with the pull rod, and the moving part can drive the pull rod to do reciprocating rectilinear