A drive system control device for a working vehicle, the working vehicle comprising: an engine which is mounted to a travel machine body; a fuel injection device which is configured to inject fuel to the engine; a continuously variable transmission which is configured to shift power from the engine, and an exhaust gas purification device which is arranged in an exhaust system of the engine, wherein the drive system control device is configured: in the case that the engine operating point relating to the rotating speed and the torque of the engine is in a low-speed and low-torque side incapable of self-renewing the exhaust gas purification device, and an engine operating point in the high-speed and low-torque side capable of self-renewing the exhaust gas purification device exists, to change the engine operating point to a high-speed and low-torque side capable of self-renewing the exhaust gas purification device, and to change and regulate a change gear ratio of the continuously variable transmission in such a manner that a vehicle speed of the travel machine body is not changed, wherein at the engine operating point in the high-speed and low-torque side, the self-renewal of the exhaust gas purification device is allowed under a condition that an output horsepower is equal to that at the engine operating point in the low-speed and low-torque side, wherein a renewing device for burning a particulate matter in the exhaust gas purification device is provided, wherein the drive system control device is configured: in the case that the engine operating point relating to a rotating speed and a torque of the engine is in the low-speed and low-torque side incapable of self-renewing the exhaust gas purification device, to actuate the renewing device when the output horsepower is equal to that at the engine operating point in the low-speed and low-torque side, and the engine operating point in the high-speed and low-torque side capable of self-renewing the exhaust gas purification device does not exist, so as to increase an exhaust gas temperature of the engine. an engine which is mounted to a travel machine body; a fuel injection device which is configured to inject fuel to the engine; a continuously variable transmission which is configured to shift power from the engine, and an exhaust gas purification device which is arranged in an exhaust system of the engine, wherein the drive system control device is configured: in the case that the engine operating point relating to the rotating speed and the torque of the engine is in a low-speed and low-torque side incapable of self-renewing the exhaust gas purification device, and an engine operating point in the high-speed and low-torque side capable of self-renewing the exhaust gas purification device exists, to change the engine operating point to a high-speed and low-torque side capable of self-renewing the exhaust gas purification device, and to change and regulate a change gear ratio of the continuously variable transmission in such a manner that a vehicle speed of the travel machine body is not changed, wherein at the engine operating point in the high-speed and low-torque side, the self-renewal of the exhaust gas purification device is allowed under a condition that an output horsepower is equal to that at the engine operating point in the low-speed and low-torque side, wherein a renewing device for burning a particulate matter in the exhaust gas purification device is provided, wherein the drive system control device is configured: in the case that the engine operating point relating to the rotating speed and the torque of the engine is in a low-speed and low-torque side incapable of self-renewing the exhaust gas purification device, and an engine operating point in the high-speed and low-torque side capable of self-renewing the exhaust gas purification device exists, to change the engine operating point to a high-speed and low-torque side capable of self-renewing the exhaust gas purification device, and to change and regulate a change gear ratio of the continuously variable transmission in such a manner that a vehicle speed of the travel machine body is not changed, wherein at the engine operating point in the high-speed and low-torque side, the self-renewal of the exhaust gas purification device is allowed under a condition that an output horsepower is equal to that at the engine operating point in the low-speed and low-torque side, wherein a renewing device for burning a particulate matter in the exhaust gas purification device is provided, wherein the drive system control device is configured: in the case that the engine operating point relating to a rotating speed and a torque of the engine is in the low-speed and low-torque side incapable of self-renewing the exhaust gas purification device, to actuate the renewing device when the output horsepower is equal to that at the engine operating point in the low-speed and low-torque side, and the engine operating point in the high-speed and low-torque side capable of self-renewing the exhaust gas purification device does not exist, so as to increase an exhaust gas temperature of the engine.