Provided are a production method of a pregabalin-containing composition, which suppresses crystallization of pregabalin, and a pregabalin-containing composition that shows suppressed crystallization of Pregabalin. The production method of the pregabalin-containing composition of the present invention contains steps of:(1) dissolving pregabalin in an aqueous solution of an acid to prepare an aqueous solution of a salt of pregabalin； (2) mixing the aqueous solution of pregabalin salt and a hydrophilic resin to prepare a mixture thereof； and (3) concentrating the mixture； wherein the acid has an acid dissociation constant lower than that of pregabalin.本發明課題在於提供一種可抑制普瑞巴林的結晶化的含普瑞巴林之組成物的製造方法，及可抑制普瑞巴林的結晶化的含普瑞巴林之組成物。解決手段為，本發明之含普瑞巴林之組成物的製造方法，其特徵為，具有：步驟(1)，係將普瑞巴林溶解於酸的水溶液，而準備普瑞巴林的鹽之水溶液；步驟(2)，係將前述普瑞巴林的鹽之水溶液與親水性樹脂混合，而準備混合液；及步驟(3)，係將前述混合液濃縮，前述酸的酸解離常數係低於普瑞巴林的酸解離常數。
