The purpose of this study was to determine the effects of taurine supplementation and taurine depletion on blood glucose and blood lipid concentrations in insulin-treated diabetic rats. Four groups of Sprague-Dawley male rats were fed the purified diet for 3 weeks : nontaurine-supplemented diabetic rats(E0), nontaurine-supplemented diabetic rats with insulin treatment(E0+I), 1% taurine-supplemented diabetic rats with insulin treatment(E1+I) and taurine-depleted diabetic rats with insulin treatment(EA+I). Diabetes was induced by streptozotocin injection(50㎎/㎏ B.W.). Isophane insulin was given subcutaneously into the abdominal wall of the diabetic rats(4 unit/rat/day). E1+I were supplemented with 1% taurine in drinking water. To induce taurine depletion, EA+I were treated with 5% β-alanine in drinking water. E1+I had significantly higher body weight compared to that of E0. The food intakes of E1+I and E0+I were significantly decreased compared to that of E0. There was no significant difference in food intake between E1+I and E0+I. The water intake of rats was significantly different among the groups : E0>E0+I>E1+I>EA+I. The urine volume of E0 was significantly increased compared to those of insulin-treated groups. The blood glucose concentration of E0 was significantly increased compared to those of insulin-treated groups. In the oral glucose tolerance test(OGTT), E0+I and E1+I had significantly lower blood glucose concentrations compared to E0 after 30 min. Also EA+I had significantly lower blood glucose concentration compared to E0 after 60 min. The plasma triglyceride concentration of E1+I was significantly decreased compared to those of E0 and E0+I. The plasma total cholesterol and LDL-cholesterol concentrations of EA+I were significantly increased compared to those of other groups. Therefore, it may be suggested that taurine supplementation is useful for insulin-dependent diabetes in order to prevent diabetic complications such as cardiac vascular diseases. (Korean J Community Nutrition 4(1) : 103~110, 1999)