A parking lock mechanism used when a working vehicle is parked, the working vehicle comprising: a step part for locking , which is disposed at a front side of a brake step surface part of a brake pedal mechanism ; and a lock unit which is connected to the step part for locking and which locks the brake pedal mechanism at a braking position thereof by the step part for locking being stepped on characterized in that the brake pedal mechanism , a forward pedal step surface part of a forward pedal mechanism configurated in order to move the working vehicle forward, and a backward pedal step surface part of a backward pedal mechanism configurated in order to move the working vehicle backward are disposed on one of a left side floor and a right side floor of a floor with reference to a center position of the floor , the forward pedal step surface part the forward pedal mechanism and the backward pedal step surface part the backward pedal mechanism are arranged in parallel and in a left-right direction, the brake step surface part is located in the front side of a step surface part of the forward pedal mechanism and the step surface part of the backward pedal mechanism , and a pedal lever main body of the brake pedal mechanism is formed to curve with swelling out in a front direction, the step part for locking is disposed adjacent to a front side edge among peripheral edges of the brake step surface part on a basis of a direction of movement of the working vehicle , the lock unit has an engagement part which engages with an engaged part , and a linkage mechanism which connects the engagement part and the step part for locking ; and the step part for locking , the engagement part and the linkage mechanism are held at the pedal lever disposed below the brake step surface part , the engaged part is disposed on a frame , which is located below the floor , of a main body of the working vehicle . a step part for locking , which is disposed at a front side of a brake step surface part of a brake pedal mechanism ; and a lock unit which is connected to the step part for locking and which locks the brake pedal mechanism at a braking position thereof by the step part for locking being stepped on characterized in that the brake pedal mechanism , a forward pedal step surface part of a forward pedal mechanism configurated in order to move the working vehicle forward, and a backward pedal step surface part of a backward pedal mechanism configurated in order to move the working vehicle backward are disposed on one of a left side floor and a right side floor of a floor with reference to a center position of the floor , the forward pedal step surface part the forward pedal mechanism and the backward pedal step surface part the backward pedal mechanism are arranged in parallel and in a left-right direction, the brake step surface part is located in the front side of a step surface part of the forward pedal mechanism and the step surface part of the backward pedal mechanism , and a pedal lever main body of the brake pedal mechanism is formed to curve with swelling out in a front direction, the step part for locking is disposed adjacent to a front side edge among peripheral edges of the brake step surface part on a basis of a direction of movement of the working vehicle , the lock unit has an engagement part which engages with an engaged part , and a linkage mechanism which connects the engagement part and the step part for locking ; and the step part for locking , the engagement part and the linkage mechanism are held at the pedal lever disposed below the brake step surface part , the engaged part is disposed on a frame , which is located below the floor , of a main body of the working vehicle . <EOS>