The aim of this study is to explore the effects of quenching and milling processing on setting property of calcium phosphate cement (CPC). For this purpose, non-quenched α-tricalcium phosphate (α-TCP) and quenched α-TCP were synthesized and their corresponding cement systems were prepared. The particle size of α-TCP powder was introduced as a variable. Then, setting properties of these CPC systems were estimated. By a comparison between non-quenched CPC and the quenched one, it is found that milling processing mainly influences the initial setting stage by decreasing reactant particle size whereas the quenching treatment affects the final setting stage by changing α-TCP content, which supports that CPC setting initially depends on the surface area of reactants and subsequently on the diffusion through the hydrated layer formed around the reactants.