The three-dimensional finite element method was used to analyze the influence of the thickness change of Sampave stress absorbing layer on the load stress and temperature stress distribution of asphalt plus pavement structure, and it was found that Sampave stress absorbing layer can greatly reduce the load stress and temperature stress at the bottom of the pavement, which has a particularly obvious effect on the latter, improves the stress state of the entire asphalt surface structure, reduces the stress concentration degree of the bottom of the pavement, delays the formation of reflective cracks in the paving layer, and shows its unique role in anti-reflective cracks. The calculation results show that the stress absorbing layer should not be too thick, and the recommended layer thickness is 2.5±0.5 cm.