The invention discloses a modified silicon dioxide sol, manufacturing method and use of the same, and a polishing liquid containing the same. The surface of the silicon dioxide of the modified silicon dioxide sol is bonded with epoxy-group-containing silane coupling agent. Modification is performed after mixing the silicon dioxide sol, surfactant and epoxy-group-containing silane coupling agent. Among the modified silicon dioxide sol according to the invention, surfaces of the silicon dioxide particles are grafted with epoxy groups, and on the one hand it can change hydrophilicity of the silicon dioxide particles, and on the other hand it can change the interaction between the silicon dioxide particles and the surfaces of wafer or polishing pad. Due to the improvement of the two properties, it can achieve higher polishing rates of TEOS and BD, and can bring less effect on polishing of Ta and Cu.