The interaction between bupropion hydrochloride and bovine serum albumin（BSA） was studied based on 1H nuclear magnetic resonance（1H NMR） chemical shift,Longitudinal relaxation time（1H T1）,2D nuclear overhauser spectroscopy（2D NOESY） and diffusion coefficient.The results showed that the presence of BSA could resulted in the significantly decrease in the chemical shifts of bupropion protons as well as the spin-lattice relaxation time,and the increase in the NOE cross peak.The apparent dissociation constant was 0.34 mmol/L and the binding sites of bupropion molecules on BSA was 11.Therefore,the reaction of bupropion and BSA was a combination of a number of weak points.The present study is of great importance for the safe and rational use of bupropion in clinic,and the development of improved bupropion analogs.