Abstract: OBJECTIVE To establish an in vitro phototoxicity detection method for cosmetic products. METHODS Six batches of cosmetic samples sold in the market were selected. The phototoxicity concentration range was determined by exploring the cytotoxicity of the samples. Reference substances including samples and positive controls were set up and the phototoxicity was evaluated. The results were analyzed by Phototox software. RESULTS The photo irritation factor of 6 kinds of cosmetics sold in the market was ≤2, which indicated that all of them had no potential phototoxicity. The sample positive control of samples suitable for the detection of products was established. The results of sample positive control and positive control showed strong phototoxicity. CONCLUSION This method has the feasibility of evaluating the phototoxicity of cosmetics and innovates the in vitro method standard which is suitable for the situation of our country.