Sulfated zirconia has been demonstrated as an efficient catalyst for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones under microwave irradiation and conventional heating. The solid acid catalyst is found to be highly active for the one-pot condensation of aldehydes, urea and beta-dicarbonyl compound, affording variety of 3,4-dihydropyrimidin-2(1H)-ones in excellent yields with high purity. The low cost catalyst has exhibited remarkable reactivity and recycled without any significant loss of activity.