A series of CuInZn_xS_2+x QDs has been successfully synthesized via a non-injection method by varying the amine (oleylamine, dioctylamine, dodecylamine, octadecylamine) during the ZnS shell introduction on the CuInS₂ core. The effects of these amines on the photoluminescence (PL) and on the morphology of CuInZn_xS_2+x QDs were explored. The optical features and structure of the obtained CuInZn_xS_2+x QDs have been characterized by UV–visible and fluorescence spectroscopies, time resolved PL, HR-TEM, XRD and EDX. After the ZnS shell introduction at 220 °C, CuInZn_xS_2+x QDs showed greatly improved properties, the PL quantum yield can reach up to 70% using dioctylamine. The formation of CuInZn_xS_2+x QDs results in a blue shift of both the absorption and PL due to the formation of the alloyed interfacial layer at CuInS₂/ZnS during the shell growth. By increasing the reaction temperature to 250 °C (thermolysis of CuInZn_xS_2+x QDs), marked red-shifts in PL emissions accompanied by morphological changes of the nanocrystals were observed. The use of oleylamine generates 6.6 nm-sized pyramidally-shaped nanocrystals with a PL quantum yield of 22%.