Hydraulic manifold block is an important component of the hydraulic system. When drilling and milling machine was at work,hydraulic manifold block calorific value was large and temperature rise was huge so as to cause the hydraulic system great energy loss. And the numerical simulation was used for hydraulic manifold block internal pore by applying for ANSYS software FLOTRAN CFD module. The results showed the relationship between the internal pore structure parameters and partial pressure loss. While hydraulic manifold block internal channels were as the objective of study, the regime of flow inside pore was simulated and the partial pressure great loss of manifold blocks for structural optimization was analyzed. The results show that reasonable pore structure could reduce the hydraulic system pressure loss to improve the hydraulic system efficiency.