An experimental study on the selenium effects on toxicity of lead (4ppm intraperitoneal injection) in adult male rats of Spragne-Dawley strain was performed. This study was carried out to reveal the selenium effects concerning treatment and prevention of lead intoxication and differences of the selenium effects according to the administration method between oral and subcutanous. The changes of body weight, liver and kidney weight per body weight, hemoglobin values, hematocrit values, TBA values in serum, and $delta$-ALAD activity in blood were determined. The results were as follows 1. There were no significant differences among groups about the change of body weight. 2. In the liver weight per body weight, the group of Pb administration after the oral administration of selenium was significantly high, different from the group of Pb administration alone (p < 0.05). 3. There .were no significant differences among groups about the kidney weight per body weight. 4. On the hemoglobin values, the group of Pb administration with selenium was significantly high,different from the group of Pb administration alone (p < 0.05). 5. There were no significant differences among groups about the hematocrit values. 6. On TBA values in serum, all the selenium treated groups were significantly low different from the group of Pb administration alone (p < 0.01). 7. On $delta$-ALAD activity, all selenium treated groups were significantly high different from the group of Pb adminsitration alone (p < 0.01). Considering from the results of this experiment, selenium seems to reduce Pb toxicity and preventive administration of selenium seems to be also effective. And the difference of selenium effect according to the administration method between oral and subcutaneous could not be found.