To solve the problem of insufficient consideration of interlayer contact state between leveling course and asphalt pavement, a new interlayer contact factor was adopted in this paper. Based on the semi-contacted bi-layer beam mechanical model, a calculation formula was derived, and the bending test on a bi-layer beam was designed to determine the interlayer contact factors under different concrete surface treatments and spraying volume of modified asphalt condition. Meanwhile, the mechanical responses were analyzed by using the analysis software ANSYS under different interlayer contact states. The results show that the interlayer contact state under artificial chiseling treatment is the best, and the maximum value of the interlayer contact factor is 0.607． The stress state of the asphalt pavement structure in the continuous layer contact state is obviously worse than that of the complete continuous contact condition. Taking the shear stress of asphalt pavement under cutting groove measure as an example, the maximum stresses in XY and YZ directions are 0.412 MPa and 0.421 MPa, while the stresses are 0.195MPa and 0.222 MPa under the complete continuous contact condition, and the former are larger than the latter by 111% and 91%, respectively. It shows that the complete continuous contact condition is not reasonable in the design of deck pavement structure． Compared with the fully continuous state, the stress state of asphalt pavement is obviously deteriorated, which indicates that the layer of the pavement layer and the layer of the asphalt overlay can be enhanced when the pavement is laid.