Relatively monodisperse and highly luminescent Ni²⁺-doped ZnSe nanocrystals were synthesized in aqueous solution at 100ºC using the nucleation-doping strategy. The effects were investigated systemati-cally. Using 3-mercaptopropionic acid as capping ligand afforded 3.1 nm wide ZnSe:Ni quantum dots (QDs) with very low surface defect density and which exhibited the Ni²⁺related green luminescence. The post-preparative introduction of a ZnS shell at the surface of the Ni²⁺-doped ZnSe QDs improved their photoluminescence properties, resulting in stronger emission. Ni²⁺-doped ZnSe@ZnS@ZnS QDs were investigated by X-ray differaction spectroscopy(XRD), UV-visible spectroscopy, Photoluminescence spectroscopy(PL). XRD confirms Ni²⁺-doped ZnSe@ZnS@ZnS QDs nanocrystal structure. Because of the Ostwald ripening effect, UV spectrum was indicated red-shift. The absorption peak was indicated redshift. The PL of the clear green solution was monitored in the course of the nanocrystal growth.