we report the the step-wise synthesis of InP/ZnS Core-Shell QDs and the role of zinc acetate. Our method imparts InP/ZnS NCs with QYs of up to 40% and shows superior properties than those of other reported InP/ZnS NCs. The overall optical emission range can cover from 500nm to 580nm and can be tuned ~20nm by adding zinc acetate. It is expected that their biocompatible and air-stable properties can promise to replace CdSe QDs for many applications.