The invention discloses a preparation method of 1, 4-succinic acid adenosine methionine. The preparation method comprises the following steps: acidifying and filtering a fermentation solution of adenosyl methionine-producing bacteria to obtain wet thalli, drying, performing freezing and thawing treatment, and uniformly mixing a water solution of inorganic strong acid with the wet thalli; filtering an acid solution containing wall-broken thalli in a ceramic membrane, adding the water solution of inorganic strong acid, and collecting filtrate; filtering the filtrate by a nano-filtration membrane to obtain a concentrated solution A; passing through a medium polar macroporous adsorption resin column, and washing with water, thereby obtaining effluent B; passing through an H+ type macroporous weakly acidic cation exchange resin column, performing elution on the H+ type macroporous acidic cation exchange resin column with 1, 4-succinic acid, performing distributed collection, and merging effluent C; sequentially filtering a collected solution by an ultra-filtration membrane and the nano-filtration membrane; and mixing a concentrated solution D with 1, 4-succinic acid, regulating the proportion of 1, 4-succinic acid to adenosyl methionine, and drying to obtain 1, 4-succinic acid adenosine methionine. The preparation method disclosed by the invention has the advantages of simplicity in operation, relatively high product yield, white color and luster and high purity.