A braking control device for a vehicle, comprising: a first deceleration calculation unit that calculates a first estimated vehicle body deceleration by using a detection signal of a wheel speed sensor (SE2, SE3, SE4, SE5) arranged on the vehicle; a second deceleration calculation unit that calculates a second estimated vehicle body deceleration by using a detection signal of a vehicle body acceleration sensor arranged on the vehicle; and an assist control unit that initiates an assist control, which assists increasing of a braking force that is applied to a wheel of the vehicle based on operation of a brake pedal of the vehicle so that the braking force is greater than a braking force applied to the wheel just by the driver's operation on the brake pedal, when the first estimated vehicle body deceleration exceeds a first deceleration determination value (DV_st) and the second estimated vehicle body deceleration exceeds a second deceleration determination value (G_st) during operation of the brake pedal of the vehicle; the braking control device being characterized by: a gradient information acquisition unit that acquires gradient information regarding a gradient of the road surface on which the vehicle is traveling; and a reference value correction unit that corrects the first deceleration determination value (DV_st) based on the gradient information, wherein the gradient information acquisition unit acquires, as the gradient information, the gradient of the road surface on which the vehicle is traveling, the reference value correction unit corrects the first deceleration determination value (DV_st) based on the gradient, when the gradient of the road surface acquired by the gradient information acquisition unit has a positive value, the reference value correction unit corrects the first deceleration determination value (DV_st) to a greater value, and when the gradient of the road surface acquired by the gradient information acquisition unit has a negative value, the reference value correction unit corrects the first deceleration determination value (DV_st) to a smaller value. a first deceleration calculation unit that calculates a first estimated vehicle body deceleration by using a detection signal of a wheel speed sensor (SE2, SE3, SE4, SE5) arranged on the vehicle; a second deceleration calculation unit that calculates a second estimated vehicle body deceleration by using a detection signal of a vehicle body acceleration sensor arranged on the vehicle; and an assist control unit that initiates an assist control, which assists increasing of a braking force that is applied to a wheel of the vehicle based on operation of a brake pedal of the vehicle so that the braking force is greater than a braking force applied to the wheel just by the driver's operation on the brake pedal, when the first estimated vehicle body deceleration exceeds a first deceleration determination value (DV_st) and the second estimated vehicle body deceleration exceeds a second deceleration determination value (G_st) during operation of the brake pedal of the vehicle; the braking control device being characterized by: a gradient information acquisition unit that acquires gradient information regarding a gradient of the road surface on which the vehicle is traveling; and a reference value correction unit that corrects the first deceleration determination value (DV_st) based on the gradient information, wherein a gradient information acquisition unit that acquires gradient information regarding a gradient of the road surface on which the vehicle is traveling; and a reference value correction unit that corrects the first deceleration determination value (DV_st) based on the gradient information, wherein the gradient information acquisition unit acquires, as the gradient information, the gradient of the road surface on which the vehicle is traveling, the reference value correction unit corrects the first deceleration determination value (DV_st) based on the gradient, when the gradient of the road surface acquired by the gradient information acquisition unit has a positive value, the reference value correction unit corrects the first deceleration determination value (DV_st) to a greater value, and when the gradient of the road surface acquired by the gradient information acquisition unit has a negative value, the reference value correction unit corrects the first deceleration determination value (DV_st) to a smaller value.