A vehicle (1, 501) equipped with a transmission, the vehicle (1, 501) comprising: a transmission which changes rotational driving power of a traveling driving power source; a shift operation member configured to be operated by a rider; a manual shift driving force transmission mechanism which transmits an operation force generated by the rider's operation of the shift operation member, to the transmission, as a shift driving force for a shift operation of the transmission; a transmission actuator (22, 222) which generates a driving force; and an automatic shift driving force transmission mechanism (24, 124, 224, 324) which transmits the driving force generated by the transmission actuator to (22, 222) the manual shift driving force transmission mechanism, as the shift driving force, wherein the automatic shift driving force transmission mechanism (24, 124, 224, 324) includes a one-direction transmission section (31, 131, 231, 331, 431) which prevents transmission of an operation of the manual shift driving force transmission mechanism to the transmission actuator (22, 222), the operation of the manual shift driving force transmission mechanism being caused by the rider's operation of the shift operation member, the one-direction transmission section (31, 131, 231, 331, 431) being configured to transmit the driving force generated by the transmission actuator (22, 222) to the manual shift driving force transmission mechanism characterized in that the automatic shift driving force transmission mechanism (24, 124, 224, 324) includes: an engaged member (32, 132, 232, 432) which is operative in response to an operation of the transmission actuator (22, 222) and is provided with an engaged part (32a, 132a, 232a, 432a), and an engagement member (33, 133, 233) which is operative in response to the operation of the manual shift driving force transmission mechanism and is provided with an engagement part (33a, 133a, 233a) which is engageable with the engaged part (32a, 132a, 232a, 432a), and in that the one-direction transmission section (31, 131, 231, 331, 431) includes an allowance part (35, 135, 235, 435) formed between the engaged part (32a, 132a, 232a, 432a) and the engagement part (33a, 133a, 233a), in an operation direction of the engagement member (33, 133, 233) which is operative in response to the operation of the manual shift driving force transmission mechanism. a transmission which changes rotational driving power of a traveling driving power source; a shift operation member configured to be operated by a rider; a manual shift driving force transmission mechanism which transmits an operation force generated by the rider's operation of the shift operation member, to the transmission, as a shift driving force for a shift operation of the transmission; a transmission actuator (22, 222) which generates a driving force; and an automatic shift driving force transmission mechanism (24, 124, 224, 324) which transmits the driving force generated by the transmission actuator to (22, 222) the manual shift driving force transmission mechanism, as the shift driving force, wherein the automatic shift driving force transmission mechanism (24, 124, 224, 324) includes a one-direction transmission section (31, 131, 231, 331, 431) which prevents transmission of an operation of the manual shift driving force transmission mechanism to the transmission actuator (22, 222), the operation of the manual shift driving force transmission mechanism being caused by the rider's operation of the shift operation member, the one-direction transmission section (31, 131, 231, 331, 431) being configured to transmit the driving force generated by the transmission actuator (22, 222) to the manual shift driving force transmission mechanism characterized in that the automatic shift driving force transmission mechanism (24, 124, 224, 324) includes: an engaged member (32, 132, 232, 432) which is operative in response to an operation of the transmission actuator (22, 222) and is provided with an engaged part (32a, 132a, 232a, 432a), and an engagement member (33, 133, 233) which is operative in response to the operation of the manual shift driving force transmission mechanism and is provided with an engagement part (33a, 133a, 233a) which is engageable with the engaged part (32a, 132a, 232a, 432a), and in that the one-direction transmission section (31, 131, 231, 331, 431) includes an allowance part (35, 135, 235, 435) formed between the engaged part (32a, 132a, 232a, 432a) and the engagement part (33a, 133a, 233a), in an operation direction of the engagement member (33, 133, 233) which is operative in response to the operation of the manual shift driving force transmission mechanism. an engaged member (32, 132, 232, 432) which is operative in response to an operation of the transmission actuator (22, 222) and is provided with an engaged part (32a, 132a, 232a, 432a), and an engagement member (33, 133, 233) which is operative in response to the operation of the manual shift driving force transmission mechanism and is provided with an engagement part (33a, 133a, 233a) which is engageable with the engaged part (32a, 132a, 232a, 432a), and in that the one-direction transmission section (31, 131, 231, 331, 431) includes an allowance part (35, 135, 235, 435) formed between the engaged part (32a, 132a, 232a, 432a) and the engagement part (33a, 133a, 233a), in an operation direction of the engagement member (33, 133, 233) which is operative in response to the operation of the manual shift driving force transmission mechanism.