The property and preparation process of cold patch asphalt modified with waterborne epoxy resin were studied to improve the properties of existing conventional patch asphalt. Firstly performance evaluation method of cold patch asphalt was proposed based on the requirements analysis of pavement pit mending. Then the influences of waterborne epoxy, curing agent content and preparation process on cold patch asphalt properties were investigated. The improvements of viscosity, adhesive, storage stability and properties of evaporation residue were analyzed. In the end, the composition and preparation process of cold patch asphalt were proposed. The results show that the properties of cold patch asphalt are significantly improved by using waterborne epoxy resin. In addition, considering workability, storage stability and pavement performance of the cold patch mixture, the best content of waterborne epoxy resin is determined as 1%2%（by mass）, the optimal mass ratio of waterborne epoxy resin to curing agent is 3∶1; the preparation temperature of cold patch asphalt is about 110120℃ and preparation time is 30min(before blending)+5min(after blending).