The subject of the present invention is to provide a hardening accelerator for a starch gelatinized dough capable of accelerating hardening of the starch gelatinized dough without damaging original flavor or mouthfeel of starch gelatinized food, a manufacturing method of a gelatinized starch dough or starch gelatinized food using the hardening accelerator, and a starch gelatinized dough or starch gelatinized food obtained by the manufacturing method. To solve the problem, by providing a starch gelatinized dough containing hardening accelerator with a partial degradation products of starch having a hydrolysis rate below 8% that serves as an effective ingredient, there are provided a manufacturing method of starch gelatinized dough characterized by adding the aforementioned hardening accelerator, and a manufacturing method of starch gelatinized food characterized by adding the aforementioned hardening accelerator.本發明係以提供一種不會損失澱粉糊化食品原本的風味或口感,可促進澱粉糊化麵團之硬化的澱粉糊化麵團用硬化促進劑、使用前述硬化促進劑的澱粉糊化麵團或澱粉糊化食品之製造方法、及以前述製造方法而得的澱粉糊化麵團或澱粉糊化食品為課題。解決手段為,藉由提供一種含有水解率為8%以下的澱粉部分分解物作為有效成分而成的澱粉糊化麵團用硬化促進劑、以添加前述硬化促進劑為特徵的澱粉糊化麵團之製造方法、以添加前述硬化促進劑為特徵的澱粉糊化食品之製造方法,來解決上述課題。