This study addresses the effect of the coatings prepared from aramid nanofibers (ANFs) on the surface treatment of aramid fiber and reinforced polycarbonate (PC) composite (AF/PC). Aramid fiber's smooth, inert surface bonds poorly with polycarbonate. In this research, the PC‐ANF coating was made by the PC/CH2Cl2 solution, which was modified by aramid nanofibers to improve the interfacial adhesion and compatibility of aramid fiber/PC composites. What's more, the silane (KH570) was added to improve the dispersion and interfacial strength of ANF and PC. The results showed the water contact angle of the aramid fiber modified by PSi‐ANF coating was reduced, indicating the modified fiber has a better wettability. The interfacial bonding strength between PC and aramid fiber increased by 77.2%. The AF/PC composites were prepared by hot‐compression, which the aramid fiber wovens treated with P‐ANF coating, PSi‐ANF coating. The tensile strength, flexural strength, interlaminar shear strength, and impact strength of the AF/PC composite reinforced by AF treated with PSi‐ANF containing 2.0 wt% ANF increased by 62.0%, 81.9%, 49.5%, and 27.6%, respectively. Therefore, this study demonstrates that incorporating ANF interphase may offer an innovative and practical way for enhancing the interface bonding properties of aramid‐reinforced composites.