Abstract: In this paper,a new method for catalytic synthesis of chalcones from substituted acetophenone and substituted benzaldehyde in polyphosphoric acid/concentrated sulfuric acid system was proposed,and the reaction conditions were optimized. The results showed that the optimized reaction conditions were determined as polyphosphoric acid of 5 equiv. and concentrated sulfuric acid of 20 equiv.,with 1,4-dioxane as solvent at 90 °C for 2 h under nitrogen protection. Twelve chalcones were synthesized with good yield. All target compounds were characterized by IR,HRMS,¹H NMR and ¹³C NMR.