In this paper, amino capped CdSe/ZnS quantum dots (QDs) were immobilized on the 11- mercaptoundecanoic acid (MUA) self-assembled Au surface (SAM/Au) by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC). Atomic force microscopy (AFM), fluorescence imaging and electrochemistry were employed to characterize the surface. The results showed that CdSe/ZnS QDs were immobilized on the surface of SAM/Au successfully. Based on this method, the fluorescence of the QDs on the SAM/Au was monitored on-line.