Aiming at the problem that the accuracy of the actual braking deceleration of the urban rail train is low under current theoretical deceleration open-loop control mode, a closed-loop braking control method is proposed based on parameter estimation. The actual braking force deviations caused by the additional running resistance when the train is running on ramps and curves and the change of friction coefficient of friction pair are taken as an equivalent total disturbance suffered by the train during braking. Then, taking the train deceleration and braking cylinder pressure as the inputs, the gradient estimation approach is adopted to solve the total disturbance. According to the estimated value of the total disturbance, the control target of train braking force is modified online to realize the closedloop control of the urban rail train braking force. In order to facilitate the programming in the actual electronic braking control unit of the braking system, the above control algorithm is discretized. The simulation and hardware-in-the-loop test results show that the parameter estimation algorithm can estimate both constant disturbance and variable disturbance, and the convergence rate of the estimated value is positively correlated with the estimator coefficient. However, when the coefficient increases to greater than 1, the convergence rate tends to saturation. This braking force closed-loop control algorithm can improve the tracking performance of the actual train deceleration to the target value. When the slope of the ramp changes according to sinusoidal law and at the same time the actual friction coefficient changes with the velocity, the deceleration deviation of the closed-loop control decreases from 0. 36 m/ s 2 to 0. 08 m/ s 2 . Moreover, when sliding occurs during braking, anti-skid control and braking force closed-loop control still can be compatible well, and the changes of the sliding axle speed, brake cylinder pressure and actual train deceleration meet the expectations.