The expression of SMP30 having multifunctions is decreased with ageing in almost all organs. The amino acid sequence of SMP30 is highly conserved among various species. Intracellular localization of SMP30 is both in cytoplasm and nucleus. Since a part of SMP30 is phosphorylated , we determined phosphorylation sites by proteomic analysis. In addition SMP30 catabolizes organophosphates in the presence of cationic ions except calcium ion. Although SMP30 has been thought to be a calcium-binding protein, our study showed no eveidence on its binding to calcium ion. Another critical function of SMP30 on oxidative stress will be discussed. Our study confirmed the critical role of SMP30 as an anti-ageing.