A working machine comprising a traveling vehicle and a working device, the traveling vehicle including a transmission case and a PTO shaft protruding from the transmission case, the working machine comprising: a structure body attached to a side of the transmission case from which the PTO shaft protrudes; and a generator attached to the structure body, the structure body including: a first portion (25a, 25b) attached to the transmission case; a second portion (251, 252) to which the working device is attached; a third portion attached to the generator, the third portion having a through hole for projecting the PTO shaft; and a first side plate and a second side plate arranged separately in a vehicle width direction of the traveling vehicle, wherein the second portion (251, 252) has a first attachment portion and a second attachment portion, to which the working device is attached, the first attachment portion being arranged to one side in the vehicle width direction, and the second attachment portion being arranged to the other side in the vehicle width direction, the generator is arranged between the first side plate and the second side plate in the vehicle width direction, the third portion is formed of a rear plate arranged between the first side plate and the second side plate, the rear plate connects the first attachment portion and the second attachment portion, the generator is attached to the rear plate, a coupling device including a three-point linkage mechanism, a lift arm, and a lift cylinder is connected to the transmission case the structure body constitutes a coupling device connected to the working device and differing from the coupling device including the three-point linkage mechanism, the working device being configured to be driven by power transmitted from the PTO shaft, characterised in that a plurality of through holes used to connect the working device are formed in the first attachment portion and the second attachment portion at intervals in a vertical direction. a structure body attached to a side of the transmission case from which the PTO shaft protrudes; and a generator attached to the structure body, a first portion (25a, 25b) attached to the transmission case; a second portion (251, 252) to which the working device is attached; a third portion attached to the generator, the third portion having a through hole for projecting the PTO shaft; and a first side plate and a second side plate arranged separately in a vehicle width direction of the traveling vehicle, wherein the second portion (251, 252) has a first attachment portion and a second attachment portion, to which the working device is attached, the first attachment portion being arranged to one side in the vehicle width direction, and the second attachment portion being arranged to the other side in the vehicle width direction, the generator is arranged between the first side plate and the second side plate in the vehicle width direction, the third portion is formed of a rear plate arranged between the first side plate and the second side plate, the rear plate connects the first attachment portion and the second attachment portion, the generator is attached to the rear plate, a coupling device including a three-point linkage mechanism, a lift arm, and a lift cylinder is connected to the transmission case the structure body constitutes a coupling device connected to the working device and differing from the coupling device including the three-point linkage mechanism, the working device being configured to be driven by power transmitted from the PTO shaft, characterised in that a plurality of through holes used to connect the working device are formed in the first attachment portion and the second attachment portion at intervals in a vertical direction.