To investigate the effect of phase change materials (PCMs) on improving the thermal erosion resistance of airport pavements and to provide recommendations for selecting optimal PCMs to obtain airport pavements with longer service lives, three PCMs, PCM-G-98 (A), LB-2 (B), and TH-HC-120 (C), were purchased based on literature summaries and market research. Based on microscopic test results and the actual preparation conditions of modified asphalt, PCMs A and B were selected. Subsequently, based on a self-made high-content SBS modified asphalt (S), four groups of composite modified asphalts (S-A-5, S-A-10, S-B-5, and S-B-10) with different mass fractions were prepared. A simultaneous thermal analyzer (TG-DSC), heat storage-exothermic tests, and infrared spectroscopy (FTIR) were used to analyze the latent heat of phase change and functional group characteristics of the PCMs. A dynamic shear rheometer (DSR) was employed to analyze the rheological properties of the composite modified asphalts, and the modification mechanism was analyzed using FTIR. The results indicate that PCM C exhibits the strongest temperature regulation capacity but is not suitable for high-temperature environments, and S-A-10 presents the best thermal erosion resistance.