A transaxle device for a hybrid vehicle including an engine, a first rotating electric machine having a cylindrical shape, and a second rotating electric machine having a cylindrical shape and operable to individually transmit power of the engine and power of the first rotating electric machine to an output shaft on a drive wheel side from different power transmission paths and also to transmit the power of the engine to the second rotating electric machine, the transaxle device comprising: a connection/disconnection mechanism (20', 20'') which is provided on a first power transmission path from the first rotating electric machine to the output shaft and enables or disables the transmission of the power of the first rotating electric machine; a first rotating electric machine shaft having a left side onto which the first rotating electric machine is connected such that a bottom surface of the first rotating electric machine faces a left side of the transaxle device; a second rotating electric machine shaft having a left side onto which the second rotating electric machine is connected such that a bottom surface of the second rotating electric machine faces the left side of the transaxle device; a fixed gear which is provided on the first rotating electric machine shaft; a counter shaft which includes an idle gear (16c, 16d) normally engaging with the fixed gear; and a second fixed gear which is disposed on the counter shaft and engaging with a ring gear of a differential, wherein the connection/disconnection mechanism (20', 20'') is provided on the counter shaft, and the transaxle device being characterized in that the idle gear (16c, 16d) and the second fixed gear are disposed on the left side of the connection/disconnection mechanism (20', 20''), and wherein the number of teeth of the idle gear (16c, 16d) is larger than the number of teeth of the fixed gear. a connection/disconnection mechanism (20', 20'') which is provided on a first power transmission path from the first rotating electric machine to the output shaft and enables or disables the transmission of the power of the first rotating electric machine; a first rotating electric machine shaft having a left side onto which the first rotating electric machine is connected such that a bottom surface of the first rotating electric machine faces a left side of the transaxle device; a second rotating electric machine shaft having a left side onto which the second rotating electric machine is connected such that a bottom surface of the second rotating electric machine faces the left side of the transaxle device; a fixed gear which is provided on the first rotating electric machine shaft; a counter shaft which includes an idle gear (16c, 16d) normally engaging with the fixed gear; and a second fixed gear which is disposed on the counter shaft and engaging with a ring gear of a differential, wherein the connection/disconnection mechanism (20', 20'') is provided on the counter shaft, and the transaxle device being characterized in that the idle gear (16c, 16d) and the second fixed gear are disposed on the left side of the connection/disconnection mechanism (20', 20''), and wherein the number of teeth of the idle gear (16c, 16d) is larger than the number of teeth of the fixed gear.