The aim of this research is to propose a method to predict the strength development of concrete using equivalent age. The experiment of strength development was carried out. Ordinary Portland cement, moderate-heat Portland cement and low-heat Portland cement were used for concrete specimen. Water cement ratio was ranged from 0.3 to 0.6. Strength development of concrete cured below subzero temperature was examined too. The result showed that the apparent activation energy in equivalent age equation depends on mineral composition of cement. Furthermore, the effect of freezing on the reaction rate of strength development was shown. Consequently, the strength development of concrete can be estimated from mineral composition of cement, nominal strength of concrete and curing temperature by the method proposed in this paper.