A manual transmission (M/T) having no torque converter, which is configured to be applied to a vehicle including an internal combustion engine (E/G) and an electric motor (M/G) as power sources, comprising: an input shaft (Ai) for receiving power from the internal combustion engine; an output shaft (Ao) for outputting power to a drive wheel of the vehicle; a transmission speed change mechanism which operates, when a driver moves a shift operation member on a shift pattern to each of shift completion positions corresponding to a plurality of gear stages (1-st to 6-th), so as to establish a power transmission system between the input shaft and the output shaft such that a transmission speed reduction ratio, which is the ratio of rotational speed of the input shaft to that of the output shaft, is set to a value corresponding to a corresponding gear stage; a motor speed change mechanism which establishes a power transmission system between the input or output shaft and the electric motor and changes, without changing the transmission speed reduction ratio, a motor speed reduction ratio which is the ratio of rotational speed of the electric motor to that of the output shaft, wherein the transmission speed change mechanism is configured such that movement of the shift operation member to each of the shift completion positions corresponding to the plurality of gear stages is achieved by movement of the shift operation member to a corresponding selection position achieved by a selection operation which is an operation of the shift operation member in a left-right direction of the vehicle in a state in which no power transmission system is established between the input and output shafts, and subsequent movement of the shift operation member from the corresponding selection position to the corresponding shift completion position achieved by a shift operation which is an operation of the shift operation member in a front-rear direction of the vehicle; characterized in that the motor speed change mechanism is configured to change the motor speed reduction ratio when the position of the shift operation member which moves in the left-right direction of the vehicle during the selection operation passes through a predetermined position on the shift pattern in the left-right direction of the vehicle. an input shaft (Ai) for receiving power from the internal combustion engine; an output shaft (Ao) for outputting power to a drive wheel of the vehicle; a transmission speed change mechanism which operates, when a driver moves a shift operation member on a shift pattern to each of shift completion positions corresponding to a plurality of gear stages (1-st to 6-th), so as to establish a power transmission system between the input shaft and the output shaft such that a transmission speed reduction ratio, which is the ratio of rotational speed of the input shaft to that of the output shaft, is set to a value corresponding to a corresponding gear stage; a motor speed change mechanism which establishes a power transmission system between the input or output shaft and the electric motor and changes, without changing the transmission speed reduction ratio, a motor speed reduction ratio which is the ratio of rotational speed of the electric motor to that of the output shaft, the motor speed change mechanism is configured to change the motor speed reduction ratio when the position of the shift operation member which moves in the left-right direction of the vehicle during the selection operation passes through a predetermined position on the shift pattern in the left-right direction of the vehicle.