A rotating electric machine unit includes a rotating electric machine, a high heat generation circuit and a low heat generation circuit both of which are electrically connected with the rotating electric machine, a first cooler, a first-coolant supplier, a second cooler and a second-coolant supplier. The first cooler is configured to cool both the high heat generation circuit and the low heat generation circuit with a first coolant. The first-coolant supplier is configured to supply the first coolant to the first cooler. The second cooler is configured to cool the rotating electric machine with a second coolant. The second-coolant supplier is configured to supply the second coolant to the second cooler. The second-coolant supplier is formed integrally with a low heat generation circuit-cooling part of the first cooler. The second-coolant supplier includes a heat exchanger via which heat is exchanged between the first coolant and the second coolant.