Background : cis-Diamminedichloroplatinum(Ⅱ)(cis-platin) has been exhibited similar to bifunctional alkylating agents in the cell and known as an effective anticancer drug. Although this agent is very beneficial to the cancer patients, it may also damage to the normal cell. Many side effects were developed. Objectives : This experiments was undertaken to pursue the effect of cis-Platin on the mucous variation of the trachea. Materials and Methods : The male of Sprague-Dawley strain were used as and experimental animals. The experimental animals were killed at 1, 3 days and 1, 2 and 3 weeks after the third injection of cis-Platin was administered 1.5mg/kg to intraperitoneal injection at once a week for three weeks. The trachea was fixed to neutral formaline and stained with alcian blue(pH 1.0)-PAS, alcian blue(pH 2.5)-PAS double stains and these preparation observed with light microscope. Results : 1. In the trachea stained with alcian blue(pH 2.5)-PAS double stain, the epithelial cells were constricted in the 1 week, In the 1st day, 3rd day and 1st week, acidic mucopolysaccharide was increased but in the 2nd week, neutral mucopolysaccharide was increase. 2. In the trachea stained with alcian blue(pH 1.0)-PAS double stain, the 1st and 3rd day exhibited sulfa mucopolysaccharide with moderately or weakly positive reaction. In the 1st week the sulfa mucopolysaccharide with strongly positive reaction was increased. In the 2nd and 3rd week, the sulfa mucopolysaccharide with weakly positive and non-sulfa or neutral mucopolsaccharide with negative reaction were modified. Conclusion : It is consequently suggested that cis-Platin induces reversible toxic damage to tracheal cells including goblet cell.