To improve workability of inserting an insulation member of a stator coil of a rotary electric machine constituted by laminating magnetic steel sheets.

The stator core of rotary electric machine comprises: a stator core; insulation members 1A and 1B which isolate a tooth part of the stator core; and a coil formed by winding the tooth part with an enamel wire, wherein, since either of tip fitting parts 5 of the insulation members 1A and 1B which are to be inserted from both end parts of the stator core has a diagonal shape, workability can be improved without using an exclusive jig during insertion.