The invention provides a flavored function konjac sauce rich in decanoyl acetaldehyde and a preparation method of the flavored function konjac sauce. The preparation method comprises the following steps of (1) preparing root and leaf juice from fresh heartleaf houttuynia roots and heartleaf houttuynia leaves, adding deacetylate konjac glucomannan to obtain heartleaf houttuynia herb konjac gum liquid, and performing refrigeration for standby application; (2) selecting entire soybeans, performing hulling, performing washing, performing soaking, performing draining, adding the heartleaf houttuynia herb konjac gum liquid in a certain weight ratio, and performing refining to obtain viscous heartleaf houttuynia herb konjac soybean milk; (3) making the viscous heartleaf houttuynia herb konjac soybean milk into heartleaf houttuynia herb konjac bean curd blanks, performing dicing, performing vacuum dehydrating, and controlling the water content; and (4) performing inoculating with aspergillus oryzae for culturing, performing aerobic fermentation to obtain konjac bean curd yeast blanks, putting the konjac bean curd yeast blanks in a preserving machine to making preserved blanks, performing inoculating with lactic acid bacteria and microzymes, and performing anaerobic fermentation, so as to obtain the konjac sauce. The flavored function konjac sauce has unique fishy fragrance and rich flavor, can diminish inflammation, resist bacteria, promote urination and reinforce immunity of human bodies. The content of the decanoyl acetaldehyde in the konjac sauce is greater than 0.1g/Kg, the content of methyl-nonyl-ketone is greater than 0.21g/Kg, and the content of total flavonoids is greater than 6.0g/Kg.