A vehicular brake system comprising: a hydraulic pump that is driven by an engine mounted on a vehicle chassis to deliver hydraulic oil; a plurality of brake devices (18L, 18R, 20L, 20R) configured to apply braking forces to the vehicle chassis by the delivery of the hydraulic oil; a manual braking operation circuit in which an operator performs an operation of the brake device (18L, 18R, 20L, 20R); and an automatic brake circuit in which the operation of the brake device (18L, 18R, 20L, 20R) is performed not through the operator, the manual braking operation circuit including: at least one first accumulator (15F, 15R) configured to accumulate the hydraulic oil to be delivered from the hydraulic pump; and at least one first brake valve (22F, 22R) configured to control supply or discharge of the hydraulic oil toward the brake device (18L, 18R, 20L, 20R) from the first accumulator (15F, 15R) by a pedal operation, and the automatic brake circuit including: at least one second accumulator (25, 61F, 61R) configured to accumulate the hydraulic oil to be delivered from the hydraulic pump; at least one second brake valve (30F, 30R) configured to control supply or discharge of the hydraulic oil toward the brake device (18L, 18R, 20L, 20R) from the second accumulator (25, 61F, 61R); a control device configured to control an operation of the second brake valve (30F, 30R); and at least one brake pressure selection device (33F, 33R) configured to select hydraulic oil higher in pressure out of the hydraulic oils to be supplied from the first brake valve (22F, 22R) and the second brake valve (30F, 30R) and to output the higher hydraulic oil to the brake device (18L, 18R, 20L, 20R), wherein at least one hydraulic oil resupply device (40, 66) is provided between the first accumulator (15F, 15R) in the manual braking operation circuit and the second accumulator (25, 61F, 61R) in the automatic brake circuit, characterized in that the hydraulic oil resupply device (40, 66) is configured to resupply the hydraulic oil accumulated in the second accumulator (25, 61F, 61R) to the first accumulator (15F, 15R). a hydraulic pump that is driven by an engine mounted on a vehicle chassis to deliver hydraulic oil; a plurality of brake devices (18L, 18R, 20L, 20R) configured to apply braking forces to the vehicle chassis by the delivery of the hydraulic oil; a manual braking operation circuit in which an operator performs an operation of the brake device (18L, 18R, 20L, 20R); and an automatic brake circuit in which the operation of the brake device (18L, 18R, 20L, 20R) is performed not through the operator, the manual braking operation circuit including: at least one first accumulator (15F, 15R) configured to accumulate the hydraulic oil to be delivered from the hydraulic pump; and at least one first brake valve (22F, 22R) configured to control supply or discharge of the hydraulic oil toward the brake device (18L, 18R, 20L, 20R) from the first accumulator (15F, 15R) by a pedal operation, and at least one first accumulator (15F, 15R) configured to accumulate the hydraulic oil to be delivered from the hydraulic pump; and at least one first brake valve (22F, 22R) configured to control supply or discharge of the hydraulic oil toward the brake device (18L, 18R, 20L, 20R) from the first accumulator (15F, 15R) by a pedal operation, and the automatic brake circuit including: at least one second accumulator (25, 61F, 61R) configured to accumulate the hydraulic oil to be delivered from the hydraulic pump; at least one second brake valve (30F, 30R) configured to control supply or discharge of the hydraulic oil toward the brake device (18L, 18R, 20L, 20R) from the second accumulator (25, 61F, 61R); a control device configured to control an operation of the second brake valve (30F, 30R); and at least one brake pressure selection device (33F, 33R) configured to select hydraulic oil higher in pressure out of the hydraulic oils to be supplied from the first brake valve (22F, 22R) and the second brake valve (30F, 30R) and to output the higher hydraulic oil to the brake device (18L, 18R, 20L, 20R), wherein at least one hydraulic oil resupply device (40, 66) is provided between the first accumulator (15F, 15R) in the manual braking operation circuit and the second accumulator (25, 61F, 61R) in the automatic brake circuit, characterized in that the hydraulic oil resupply device (40, 66) is configured to resupply the hydraulic oil accumulated in the second accumulator (25, 61F, 61R) to the first accumulator (15F, 15R).