Luminescent quantum dots (QDs)-semiconductor nanocrystals were promising alternative to organic dyes for fluorescence-based applications. In this paper, we developed procedures to use mercaptoacetic acid (MAA) to modify ZnSe nanoparticles and made the nanoparticles to be soluble for the quantitative and selective determination of bovine serum albumin (BSA). Maximum fluorescence intensity was produced at pH 7.0, with excitation and emission wavelengths at 242 and 348 nm, respectively. Under optimal conditions, the straight line equation: Delta(F) = 0.38 + 0.34 C (microg/ml) was found between the relative fluorescence intensity and the concentration of BSA in the range of 9.6-124.8 microg/ml, and the limit of detection was 2 microg/ml.