A facile synthesis of some 4-hydroxychalcones (3a-3j) by the condensation of various substituted benzaldehydes and 4-hydroxyacetophenone has been described. It is prepared by Claisen-Schmidt condensation. This is a comparative study of synthesizing compounds by conventional as well as non-conventional microwave irradiation in a commercially modified microwave oven and thus confirms the possible intervention of specific (non-thermal) microwave effect. The research is focused on the remarkable reaction rate enhancement by the use of various non-conventional microwave irradiations which minimizes the time and solvents in reactions. The microwave method offers several advantages like simple procedure, fast reaction rate, mild reaction condition and improved yields as compared to conventional methods. Variety of functional groups such as nitro, chloro, dimethylamino, methoxy, methyl and hydroxy survived under the reaction conditions. The structures of newly synthesized compounds have been established on the basis of IR and 1H NMR spectral data.