Gas-phase hydration of ethene was carried out over Me(HPO4)(2).nH(2)O (Me = Ge, Zr, Ti, and Sn) catalysts at atmospheric pressure. it was found that the catalysts prepared from Sn(HPO4)(2) . 2H(2)O were highly active and selective for the title reaction. The activity of Sn(HPO4)(2) . 2H(2)O was varied by the concentration of H3PO4 in the: preparation of the catalysts. Decreased concentration:df H3PO4 led to increased surface area of the catalysts. The catalyst prepared in an aqueous solution of 3.9 mol/dm(3) H3PO4 exhibited best performance among the catalysts studied in;the hydration of ethene. The activity of the catalyst was over 20 times that of a commercial H3PO4/SiO2 catalyst, involvement of surface HPO4 in the reaction was suggested.