A vehicle brake system, comprising: a brake operation member to be operated by a driver of a vehicle; a hydraulic brake device provided for one of a front wheel and a rear wheel and configured to generate a hydraulic braking force in accordance with an operation of the brake operation member, the hydraulic braking force depending on a pressure of a working fluid; and an electric brake device provided for the other of the front wheel and the rear wheel and configured to generate an electric braking force in accordance with the operation of the brake operation member, the electric braking force depending on a motion of an electric motor; characterized in that wherein the vehicle brake system is configured to perform at least one of the following: (i) estimate that the vehicle is in the situation in which the hydraulic braking force decreases when an outside temperature is low; (ii) estimate that the vehicle is in the situation in which the hydraulic braking force decreases when an atmospheric pressure is low; and (iii) estimate that the vehicle is in the situation in which the electric braking force decreases when a temperature of the electric motor is high; and based on at least one of the estimates, the vehicle brake system is configured to: increase one of the hydraulic braking force and the electric braking force to cover the decrease of the other of the hydraulic braking force and the electric braking force, or decrease the one of the hydraulic braking force and the electric braking force in accordance with the decrease of the other of the hydraulic braking force and the electric braking force. a brake operation member to be operated by a driver of a vehicle; a hydraulic brake device provided for one of a front wheel and a rear wheel and configured to generate a hydraulic braking force in accordance with an operation of the brake operation member, the hydraulic braking force depending on a pressure of a working fluid; and an electric brake device provided for the other of the front wheel and the rear wheel and configured to generate an electric braking force in accordance with the operation of the brake operation member, the electric braking force depending on a motion of an electric motor; characterized in that wherein the vehicle brake system is configured to perform at least one of the following: (i) estimate that the vehicle is in the situation in which the hydraulic braking force decreases when an outside temperature is low; (ii) estimate that the vehicle is in the situation in which the hydraulic braking force decreases when an atmospheric pressure is low; and (iii) estimate that the vehicle is in the situation in which the electric braking force decreases when a temperature of the electric motor is high; and (i) estimate that the vehicle is in the situation in which the hydraulic braking force decreases when an outside temperature is low; (ii) estimate that the vehicle is in the situation in which the hydraulic braking force decreases when an atmospheric pressure is low; and (iii) estimate that the vehicle is in the situation in which the electric braking force decreases when a temperature of the electric motor is high; and based on at least one of the estimates, the vehicle brake system is configured to: increase one of the hydraulic braking force and the electric braking force to cover the decrease of the other of the hydraulic braking force and the electric braking force, or decrease the one of the hydraulic braking force and the electric braking force in accordance with the decrease of the other of the hydraulic braking force and the electric braking force. increase one of the hydraulic braking force and the electric braking force to cover the decrease of the other of the hydraulic braking force and the electric braking force, or decrease the one of the hydraulic braking force and the electric braking force in accordance with the decrease of the other of the hydraulic braking force and the electric braking force.