Abstract: In order to study lift-off effect of polyimide films under 308nm excimer laser irradiation, by means of experimental research, the effects of laser energy density, spot overlap rate, pulse frequency and substrate temperature on laser lift-off were investigated. The morphologies of the stripped substrates and films were observed by microscopy. The results show that, the threshold of laser lift-off energy is about 160mJ/cm². When laser energy density is about 180mJ/cm²~190mJ/cm² and spot overlap rate is 68.33%, lift-off effect is better. Increasing the substrate temperature is beneficial for laser lift-off process. This study has certain significance for the industrial application of polyimide films in the field of flexible electronics.