In this study, an application algorithm has been introduced to explore structural optimisation for gear pump housing. In the study, experimental and theoretical (analytical and numerical) methods are utilised. A commercial external spur gear pump which has 17.1 L min(-1) volumetric flow rate with maximum pressure capacity of 250 bar has been considered for an application case study. In the experimental section of the study, four pressure sensors (emitters) were placed with angle intervals of 45 degrees, 90 degrees, 135 degrees, and 180 degrees on the pump's housing to measure operating pressure values at specific pressure regions of the housing from inlet to outlet. According to experimental results of the pressure measurements, a response surface analysis (RSA) was carried out and then an estimation model (empirical equation), which could be used to calculate pressure values at any specific region of the housing, was obtained. According to the RSA results gained, it appears that the estimation model has 99.9% R-2 value which can be used for adequately predicting accurate pressures at any region of the housing. Subsequently, this estimation model has been adapted for commercial finite element method (FEM)-based engineering software and from which stress distributions on the housing were simulated three dimensionally. FEM-based simulation outputs showed that there were no failure signatures on the pump housing. As the main conclusion of the study, it is seen that an estimation model gives an adequate approach to predict pressure values at any specific pressure region of the pump housing and, especially, stress distribution results has highlighted that a structural optimisation study may be suitable for the pump housing.