Based on numerical simulation, the flood control safety of the No. 2 ogee spillway tunnel on the left bank of the Xiaolangdi Hydropower Station was analyzed from the aspects of discharge capacity, cross-sectional velocity, tunnel space, piezometric head, cavitation number and jet flow induced scouring. The simulated results were compared with a 1∶40 physical model experiment. Meanwhile, corresponding measures were proposed to solve the common safety problems during the operation of the ogee spillway tunnel. The results show that the simulated results are basically consistent with the experimental results, which indicates that it is feasible to use numerical simulation to analyze the flood control safety for the ogee spillway tunnel.