The present invention provides a method for producing hydroxyalkyl cellulose fine particles which comprises generating pulse shock wave and providing hydroxyalkyl cellulose aqueous solution to the region of the generated pulse shock wave so that the hydroxyalkyl cellulose aqueous solution is grinded and dried. Hydroxyalkyl cellulose fine particles having a volume average particle diameter within the range of more than or equal to 0.1μm to less than 15μm are obtained by the production method. In addition, solid formulation having a good tensile strength and degradability is obtained by mixing the hydroxyalkyl cellulose fine particles with a principal agent and then formulating the mixture as a tablet.本發明提供一種羥烷基纖維素微粒子之製造方法，其包括：產生脈衝衝擊波，供給羥烷基纖維素水溶液至該脈衝衝擊波之產生區域，而將羥烷基纖維素水溶液粉碎乾燥。藉由該製造方法，獲得體積平均粒徑為0.1 μm以上且未達15 μm之羥烷基纖維素微粒子。又，將該羥烷基纖維素微粒子與主劑混合，並將該混合物壓錠，藉此獲得拉伸強度及崩散性優異之固體製劑。
