This study was undertaken to investigate the effect of superoxide dismutase(SOD) to sunburn cell production and development of UV-induced ear swelling reaction in mouse skin after ultraviolet irradiation. In this study, a total of 60 ICR female albino haired mice were used and divided into two groups, A(UVB: 150mJ/cm) and B(UVB:300mJ/cm). Groups of mice were injected intravenouly with SQD(300mJ,/1000cm) just befare UVR and after completion of UVR. The results were as follows . 1. The number of sunburn cells was significantly decreased by injection of SOD (300ug.1000ug)(p<0.05). 2. The number of sunburn cells in a group of mice which was given SOD 1000ug was significantly decreased more than in SOD 300pg(p<0.05). 3. Ear swelling reaction was not significantly suppressed by injection of SOD(300 Pa. 100SC)(p<0 05)