<p>The interval-pooled stepped spillway efficiently dissipates energy, reducing the size of the downstream basin and lowering investment costs. However, the flow regime in interval-pooled stepped spillways is complex, and the incoming flow pressure can threaten the step plates and baffles. Currently, there is limited research on the pressure distribution on the bottom plates and baffles of interval-pooled stepped spillways. In this paper, the flow in an interval-pooled stepped spillway was simulated, and the pressure distribution was analyzed using the RNG <i>k-ε</i> model combined with the Volume of Fluid (VOF) method. The reliability of the numerical simulation results is confirmed, and it is verified that the accuracy of the numerical model is within a reasonable range. The results show that the pressure distribution and flow structure of <i>d/h</i> = 0.25 and <i>d/h</i> ≥ 0.50 are different. The formation of “pseudo-weir” may be the main reason for the difference. At high flow rates, the larger average pressure occurs on the horizontal step surfaces with pool (HP) and no-pool vertical step surfaces (NV) of the pooled step section; while the negative pressure is found in vertical step surfaces with pool (VP) where the step is connected to the pool. Additionally, the extent of the negative pressure is related to the flow rate and pool height. A predictive expression for the starting position of negative pressure was established for the flow range of 1.9 &lt; <i>d</i>_<i>c</i><i>/h</i> &lt; 3.24.</p>