The nasal foreign body may be encountered most frequently on careless or curious young children and babies, or may be found in insane adult, and or may remain in the nose after local treatment or surgical procedure on the nose. Within few hours or days, nasal foreign body induce inflammation of nasal mucosa, which is spread to paranasal sinus. The auther performed experimental study with insertion of various foreign bodies (paper, grass and bean) into the nasal cavity of white rabbit of duration of 5 and 10 days, and study the histopathological change of mucosa of nose and maxillary sinus. The following results were obtained : 1) In paper group, the histopathological change of the nasal mucosa was more severe, and acute suppurative inflammation was more evident and diffuse. 2) In grass group, the histopathological change was localized, more necrotizing, and much lymphoid follicle was noted in the submucosal tissue layer. 3) The bean group showed more hemorrhagic, foreign body giant cell, and mucosal compression and atropy. The inflammatory change was on the tip of the mucosal fold. 4) The degree of histopathological change of the maxillary sinus was dependent on the experimental duration in paper and grass group as nasal mucosa. But no considerable change was found in bean group. 5) In early stage, circulatory disturbance such as edema and congestion, ulceration of ciliated epithelium showed mild to moderate degree of change. Goblet cell hyperplasia was increased in relation to duration. 6) The polymorphonuclear leucocyte was over moderate degree in early stage, but later lymphocyte was increased instead of polymorphonuclear leucocyte. 7) The mucosal compression and atropy was more prominent in grass and bean group.