In this paper, the combination of experimental and finite element software simulation is used to analyze the bending resistance of steel-concrete composite cross-section thin steel composite pipe beams with different interlayer concrete strength. The outer layer is made of thin-walled stainless steel pipe, the inner layer is steel pipe, and the three test pieces of concrete strength grades C20, C40 and C60 are respectively sprayed in the middle of the double-walled pipe, and the test pieces are loaded by the grading loading method, and the test results are limited. The results of the meta-software simulation are consistent. The results show that with the increase of concrete strength, the flexural capacity of the specimen and the ductility increase, and large plastic deformation can occur to absorb energy. The test results obtained can provide a basis for future research.