The invention discloses an inner expansion pressing mould of a motor stator core. A technical scheme for solving technical problems of the invention is as follows: the inner expansion pressing mould of the motor stator core includes a steel supporting tube, a supporting plate having an inner cavity is axially fixed on a surface of the steel supporting tube, a steel plate having a T-shaped groove is fixed at the other side of the contact part between the supporting plate and the steel supporting tube, a movable location block is placed in the T-shaped groove, a lifting jack is placed in the inner cavity of the supporting plate, and a head of the lifting jack acts on the movable location block by the supporting plate and the steel plate having the T-shaped groove. The inner expansion pressing mould of the motor stator core has the advantages of rational design, low manufacturing cost, simple and convenient operation, accurate location, high processing precision of work pieces, and the like.