The purpose of the present invention is to provide an intraoral disintegrating tablet (an ultrafast disintegrating tablet) that has an extremely high disintegrability (a short disintegration time) and a high tablet hardness and a simple method whereby the aforesaid ultrafast disintegrating tablet can be manufactured without performing any troublesome procedure such as freeze drying. The present invention relates to: an intraoral disintegrating tablet that has a disintegration time in water of shorter than 15 seconds and a tablet hardness of 10 N or greater said disintegrating tablet containing a first disintegrant component comprising an acid type carboxymethylcellulose； a method for manufacturing the intraoral disintegrating tablet； a disintegrating granular composition to be used in the manufacturing method etc.
