A new method to detect the cefamandole in drug by fluorescence quenching of bovine serum albumin(BSA)was investigated. The BSA had a strong intrinsic fluorescence because of tryptophan and tyrosine,and cefamandole(CEF) solution itself didn′t produce fluorescence,but when cefamandole combined with the BSA,the fluorescence intensity of BSA was decreased.Based on in a certain range, the fluorescence quenching of BSA in the λex = 340 nm having a good linear relationship with the concentration of cefamandole, a new method to detect the cefamandole in drug was established. The conjugate of BSA and cefamandole had a max fluorescence value at 340 nm which was found the decreased intensity of fluorescence at 340 nm was proportion to cefamandole in the range of 2.18×10-6~2.62×10-5 mol·L-1. The linear regression equation was ΔF=2.42×107CCEF-35.155 with a correlation coefficient of 0.996 9. The detection limit was 1.029 91×10-6 mol·L-1,the relative standard deviation was 0.16% and the average recovery of sample was 94.67%~98.43%.The method was simple and rapid,and could be applied to detect the trace cefamandole in drug with satisfactory results.