Abstract: Aiming at the existing problem of lagged data updates and spatial interpolation uncertainty in estimation results caused by open-pit coal mine reserves evaluation, which relies on drilling data and is hard to reflect dynamic information such as surface deformation, stope evolution and others, a reserves dynamic update method based on 3D geological model is constructed. Taking the geological modeling platform as the basis, multi-source data such as drilling, well logging, UAV/LiDAR point clouds and others are integrated to construct a stratigraphic structure framework. The attribute estimation strategy combining ordinary kriging and sequential Gaussian simulation is adopted to balance point estimation accuracy and spatial uncertainty expression; Introducing a simplified Bayesian/Kalman condition update and voxel depletion processing mechanism at the block model level to achieve local model correction when new data arrives; Simultaneously constructing a coupled coordination framework of reserves - mining and excavation - disturbance to characterize the correlation between reserves changes, mining and excavation intensity, and surface disturbances. The verification in the testing area shows that this method can improve the continuity and consistency of reserves estimation, reduce local deviation, and has the feasibility of dynamic updating, providing an achievable and interpretable technical approach for reserves management in open-pit coal mines.