Abstract: The traditional production process with soda ash as raw material to produce sodium metabisulfite was high in cost and low in profit.The sodium carbonate decahydrate was by-produced from the production of hydrazine with urea method in chlor-alkali industry.Taking the by-product sodium carbonate decahydrate to replace the soda ash in the production of sodium metabisulfite had the advantages of low raw material cost，little change in process flow，and good economic benefit etc..Meanwhile，it also provided a new way for the application of sodium carbonate decahydrate.

Key words: sodium carbonate decahydrate, sodium metabisulfite, production process