A series of tetrahydroquinazoline derivatives were synthesized by cyclization condensation in aqueous medium with 1-butyl-3-methylimidazole tetrafluoroborate as catalyst, aromatic amine and 2-aminobenzaldehyde as raw materials. By exploring the reaction conditions, the optimal conditions are determined as follows: With 0.2 mmol 2-(1-pyrrolide) benzaldehyde (Ⅰa), 0.4 mmol aromatic amine (Ⅱa), 30% (based on the amount of Ⅰa, the same below) catalyst, 1 mL H2O, at 90 ℃ for 6 h, the highest yield of 81% of the product was obtained. At the same time, the universality of the substrate was investigated, and 19 tetrahydroquinazoline derivatives were synthesized from a wide range of substrates.