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Ecdysteroid-phosphate Phosphatase is the first structure of a steroid phosphate phosphotase containing alpha beta folds common to members of the two histidine -Phosphatase superfamily with strong homology to the Suppressor of T-cell receptor signaling-1 protein. The putative EPPase PGM active site contains signature residues shared by 2H-phosphatase enzymes, including a conserved histidine that acts as a nucleophile during catalysis. The physiological substrate ecdysone 22-phosphate was modeled in a hydrophobic cavity close to the phosphate-binding site. EPPase PGM shows limited substrate specificity with an ability to hydrolyze steroid phosphates, the phospho-tyrosine substrate analogue para-nitrophenylphosphate and pTyr-containing peptides and proteins. It has been shown that new protein tyrosine phosphatase activity for EPPase. Also, EPPase and its closest homologues can be grouped into a distinct subfamily in the large 2H-Phosphatase superfamily of proteins.