A rotary electric machine comprising: a stator ; a rotor ; a case for housing the stator and the rotor , wherein the case includes an inner case portion to which the stator is fixed and an outer case portion that houses the inner case portion , the inner case portion includes a first coupling portion , the outer case portion includes a second coupling portion , the first coupling portion and the second coupling portion are fixed to each other, an air chamber is formed between an outer surface of the inner case portion and an inner surface of the outer case portion , the inner case portion has a first tubular portion having an inner peripheral surface in contact with an outer peripheral surface of the stator , the outer case portion has a second tubular portion that has a tubular shape and that covers an outer peripheral surface of the first tubular portion , a coolant flow path is formed between the first tubular portion and the second tubular portion , the first coupling portion is formed so as to protrude from the first tubular portion to an inner radial side (R2) on an axial direction first side (L1), which is one side in an axial direction with respect to the stator , the second coupling portion is formed so as to protrude from the second tubular portion to the inner radial side (R2) on the axial direction first side (L1), and the air chamber includes a region formed in a space in which the first coupling portion and the second coupling portion face each other in the axial direction (L), characterized in that a breather hole that communicates the air chamber and an outside of the case is formed in the outer case portion , and the inner case portion has a communication portion that communicates a housing space in which the stator is housed and the air chamber . a stator ; a rotor ; a case for housing the stator and the rotor , wherein the case includes an inner case portion to which the stator is fixed and an outer case portion that houses the inner case portion , the inner case portion includes a first coupling portion , the outer case portion includes a second coupling portion , the first coupling portion and the second coupling portion are fixed to each other, an air chamber is formed between an outer surface of the inner case portion and an inner surface of the outer case portion , the inner case portion has a first tubular portion having an inner peripheral surface in contact with an outer peripheral surface of the stator , the outer case portion has a second tubular portion that has a tubular shape and that covers an outer peripheral surface of the first tubular portion , a coolant flow path is formed between the first tubular portion and the second tubular portion , the first coupling portion is formed so as to protrude from the first tubular portion to an inner radial side (R2) on an axial direction first side (L1), which is one side in an axial direction with respect to the stator , the second coupling portion is formed so as to protrude from the second tubular portion to the inner radial side (R2) on the axial direction first side (L1), and the air chamber includes a region formed in a space in which the first coupling portion and the second coupling portion face each other in the axial direction (L), characterized in that a breather hole that communicates the air chamber and an outside of the case is formed in the outer case portion , and the inner case portion has a communication portion that communicates a housing space in which the stator is housed and the air chamber . <EOS>