Abstract: The present application provides a method for preparing acetal carbonyl compound used as a mediate for producing ethylene glycol, which comprises a step in which a raw material acetal and a raw gas carbon monoxide go through a reactor loaded with a catalyst containing an acidic microporous silicoaluminophosphate molecular sieve, for carrying out a carbonylation reaction. In the method of the present invention, the conversion rate of the raw material acetal is high, and the selectivity of acetal carbonylation is high, and the catalyst life is long, and no additional solvent is needed in the reaction process, and the reaction condition is relatively mild, and the process is continuous, showing the potential for industrial application. Moreover, the product of acetal carbonyl compound can be used for producing ethylene glycol by hydrogenation followed by hydrolysis.