[Purposes] The current treatment of manhole covers and the asphalt pavement around manholes is ineffective, and the diseases are still frequent after repair, which has become a persistent disease affecting road performance. [Methods] In order to analyze the influence range and degree of manhole covers on the asphalt pavement around manholes in urban roads, typical road sections were selected as research subjects. The damage condition and resilient modulus of asphalt pavement around manholes were tested. The damage characteristics were statistically analyzed, and the damage degree was assessed to reveal the modulus decay pattern of the asphalt pavement around manholes. Based on the threshold effect analysis method, the critical inflection point of the modulus decay curve was determined. Accordingly, a simulation model of the manhole-road structure was constructed for three conditions: no damage, unrepaired, and repair. This model was used to quantitatively analyze the influence of modulus decay on the service performances of the asphalt pavement around manholes. [Findings] Before and after repair, the surface damage rates of the asphalt pavement around manholes were 7.5% and 11.7%, respectively, with the cracks concentrated within 200 mm of the manhole cover edge. Compared to normal pavement, the modulus of the surrounding asphalt pavement decreased by up to 44%, which can be fitted by an inverse exponential function model. The influence range of the manhole cover on the asphalt pavement around manholes before and after repair was approximately 680 mm and 440 mm, respectively, both of which were larger than the repair range determined by the surface damage method. Simulation results showed that after damage to the asphalt pavement around manholes, the surface deflection increased by 4.5%, and the difference in the upper and lower layer top compression stress decreased by 57.9%. As depth increased, the stress dissipation effect worsened. The fatigue cracking life of the surface layer of the asphalt pavement with no damage around manholes was approximately 4.7 times that of the unrepaired asphalt pavement, and 3.6 times that of the repaired asphalt pavement. [Conclusions] The research results provide a theoretical basis for the maintenance and treatment of the asphalt pavement around manholes, which helps to extend the service life of the road and improve its safety and comfort.