Surfur dioxide, one of the air pollutants, has been related increasing morbidity rates due to respiratory damages. To investigate the effect of Bopaetang(補肺湯) on rats induced by exposur of $SO_2$, an experimental study was done the changes on white blood cell(W5C), the content of glycoprotein in treachea and the edema, congestion, inflammatory infiltrates of trachea. The experimental groups are the normal group, control group and sample group( administered Bopaetang to rats induced by exposur of $SO_2$). The results were as follows; 1. The change on WBC on rats induced by exposur of $SO_2$ were made significant differences in sample group compared with control group. 2. The content of Glycoprotein In trachea were made significant differences in sample group compared with control group. 3. The edema, congestion, inflammatory infiltrates of treachea were made significant differences in sample group compared with control group.