An electric vehicle driving system comprising: an electric motor serving as a power source; a transmission that includes a main shaft, wherein the main shaft is directly connected to the electric motor; a casing accommodating the electric motor and the transmission, wherein the casing includes a side cover that is arranged at an axial end of the electric motor that is opposite to the axial end of the electric motor that faces the transmission, and the side cover covers a side surface portion in an axial direction of the electric motor, wherein the side cover forms an oil path that supplies a cooling lubricant to a heat generating portion of the electric motor, wherein the heat generating portion of the electric motor is a coil of a substantially annular stator, and characterized in that the side cover includes plural ejecting holes that eject the lubricant toward an upper semicircular portion of the stator, that the side cover is formed of a resin, and that the oil path includes a radial oil feeding path that is formed in the radial direction from the center of the side cover; and a semicircular oil feeding path that communicates with the radial oil feeding path and is formed so as to correspond to the upper semicircular portion of the stator, the oil path communicating with an oil path provided in a shaft of the transmission, and that an oil feeding hole of the main shaft is formed at a center of the main shaft and extends in an axial direction of the main shaft, that the path includes an axial extension portion extending in an axial direction from the radial oil feeding path at the center of the side cover and the axial extension portion is provided with a lubricant supplying hole, that the lubricant supplying hole communicates with the oil feeding hole of the main shaft, and that the plural ejecting holes are circumferentially arranged in the semicircular oil feeding path at intervals. an electric motor serving as a power source; a transmission that includes a main shaft, wherein the main shaft is directly connected to the electric motor; a casing accommodating the electric motor and the transmission, wherein the casing includes a side cover that is arranged at an axial end of the electric motor that is opposite to the axial end of the electric motor that faces the transmission, and the side cover covers a side surface portion in an axial direction of the electric motor, wherein the side cover forms an oil path that supplies a cooling lubricant to a heat generating portion of the electric motor, wherein the heat generating portion of the electric motor is a coil of a substantially annular stator, and characterized in that the side cover includes plural ejecting holes that eject the lubricant toward an upper semicircular portion of the stator, that the side cover is formed of a resin, and that the oil path includes a radial oil feeding path that is formed in the radial direction from the center of the side cover; and a semicircular oil feeding path that communicates with the radial oil feeding path and is formed so as to correspond to the upper semicircular portion of the stator, the oil path communicating with an oil path provided in a shaft of the transmission, and that an oil feeding hole of the main shaft is formed at a center of the main shaft and extends in an axial direction of the main shaft, that the path includes an axial extension portion extending in an axial direction from the radial oil feeding path at the center of the side cover and the axial extension portion is provided with a lubricant supplying hole, that the lubricant supplying hole communicates with the oil feeding hole of the main shaft, and that the plural ejecting holes are circumferentially arranged in the semicircular oil feeding path at intervals.