Abstarct: In recent decades, deep eutectic solvents (DES) have emerged as a significant tool in green chemistry. Due to their simplicity and accessibility, these solvents are considered a suitable alternative to organic solvents. In this study, a new method for the synthesis of pyrano[2,3-d]pyrimidine derivatives through a three-component reaction of 4,6-dihydroxypyrimidine, aromatic aldehydes, and malononitrile in the presence of choline chloride/oxalic acid as a catalyst in ethanol is reported. The results show that the highest yield is obtained by using 20 mol% of catalyst and temperature of 80°C. The advantages of this method include short reaction time, high yield, use of green solvent, and easy purification of the product.