An oil pump is the core of machinery lubrication system components. With the base of the outside gear engine oil pump,the paper built a method in finite element and theory analysis aiming at the oil pump machine manufacture stuck phenomenon. The numerical simulation analysis to inner flow field of the pump was conducted by adopting CFX,with the Ansys Workbench,the machine solid thermosetting coupling structure analysis for the driven part of hot oil pump was studied,and combined with Matlab curve fitting interpolation,the stuck causes were found; On the basis of hydrodynamic pressure lubrication,the minimum oil film thickness,temperature rise and the bearing capacity were as the key analysis factors,ultimately the appropriate solutions were concluded aiming at stuck reasons. Finally with the corresponding physical experiment for verifying the improvement experiment,the rationality analysis of the results was verified,which provided the technical reference to model change of the future engine oil pump.