In order to research the raw material properties and modification effects of Venezuela rock asphalt, the physicochemical properties of Venezuela rock asphalt and its modified asphalt were tested in laboratory. The physical properties, asphalt content (mass proportion), asphalt four-component and mineral composition were analyzed for its raw materials. The influence rules were evaluated for different mixing amounts of Venezuela rock asphalt on the performances of its modified asphalt, and the modification mechanism was revealed. The results show that the asphalt content in Venezuela rock asphalt is at up to more than 95%, and the content of asphaltene and colloid exceeds 80%, which is a kind of hard asphalt with high degree of polymerization. Its minerals mainly contain SiO2, CaSO4, CaS and a small amount of CaCO3. Using for modifier, it can significantly enhance the viscosity and deformation resistance of its modified asphalt, and improve the pavement performances such as high temperature, ageing resistance, moisture damage resistance and temperature sensitivity etc. However, it has an adverse effect on low temperature performance. Then the mixing amount of Venezuela rock asphalt should be controlled within 15% of the total mass of its modified asphalt. Venezuela rock asphaltand the base asphalt have similar functional groups, both of them can not only mix well, but also there is no obvious chemical reaction to belong to a physical modification. Therefore, Venezuela rock asphalt is more suitable for wet mixing modified process to prepare the low-grade hard asphalt which can be more suitable for the southern hot and humid areas.