To promote the anti-ageing performance of asphalt, layered double hydroxides (LDHs) modified by propyl trimethoxylsilane (MPMS) was prepared and applied to modify asphalt. Fourier transform infrared spectroscopy (FTIR) showed that MPMS was chemically-grafted on the surface of LDHs. The interaction between LDHs and asphalt was significantly enhanced after MPMS organic modification, and MPMS organic LDHs (OMLDHs) exhibited better compatibility in asphalt. OMLDHs and LDHs could enhance the high-temperature properties of asphalt, particularly OMLDHs. After ageing, the properties and structure of asphalt were dramatically degenerated. The incorporation of LDHs could inhibit the oxygenic groups increase in asphalt molecules during ageing, and retard the gelatinization of colloidal structures. LDHs could alleviate the negative effect of ageing on asphalt, and improve the anti-ageing performance of asphalt. The improvement effectiveness of LDHs on the anti-ageing performance of asphalt was remarkably improved after MPMS modification.