Abstract: This invention, which involves synthetic method of 5, 5- dimethyl-2, 4-adipaldehyde-0, 0-Boron difluoride, belongs to the field of organic synthesis. Synthetic method of 5, 5-dimethyl-2, 4-adipaldehyde-0, 0-Boron difluoride is to react pinacolone and boron trifluoride diethyl ether at low temperature, and then add aqueous alkaline solution in after treatment to extract product from ether, after that, separate fluid, condense organic phase and final product is obtained. Yield of this method is 2 to 3 times higher than that in literature, and apart from that, mild reaction condition, simple procedures, easy operation, and low cost make it easy for industrial production. The product can be used directly in next step reaction without any special purification.