Objective:To study the interaction between cisplatin and bovine serum albumin ( BSA) under the simulated human physiological condition. Methods:The interaction mechanism of BSA and cisplatin was investigated by fluorescent spectrometry; the binding constant, binding site and interaction force were studied, and the interaction effects on the conformation change of BSA were investigated as well. Results:The results of fluorescent spectrometry showed that a ground state complex was formed between cisplatin and BSA, and the mechanism of fluorescence quenching was static quenching. The binding parameters of cisplatin and BSA were as follows:the binding constant was 1. 36 × 104 L·mol-1 , the binding site was 0. 991, and the interaction was mainly driven by hydrogen bonds and Van Der Waals forces. The results of synchronous fluorescent spectrometry demonstrated that the interaction influenced the micro-environments of amide acid residues. Conclusion:Cisplatin can interact with BSA and change the conformation of BSA.