In this paper, a series of pyrano[2,3-d]pyrimidine derivatives have been synthesised by the reaction of aromatic aldehydes, malononitrile and pyrimidine-4,6-diol in ionic liquid [bmim+][BF4-] at 80 °C. The structures of the products were characterised by IR, 1H NMR spectra. Compared with other methods, ionic liquid is a green solvent, which has the advantages of easier work-up, milder reaction conditions, high yields and environmentally benign procedure.