The serum and urinary uric acid and calcium were studied in 10 diabetic patients, 20 had insulin dependent diabetes mellitus [IDDM] and 20 had non insulin dependent diabetes mellitus [NIDDM]. The serum uric acid and calcium were significantly decreased, while 24 hours urinary uric acid and calcium were significantly increased in diabetic groups compared to controls. These biochemical changes were more marked in IDDM group than in NIDDM group. There was a significant negative correlation between serum and urinary uric acid in IDDM and in NIDDM group. A significant positive correlahon was also present between urinary uric acid and fasting blood glucose in both IDDM and NIDDM groups. In IDDM group only there was a significant positive correlation between urinary uric acid and urine volume. However, further large scale and follow up studies are recommended to evaluate the relevance of disturbed uric acid and calcium haomeostasis to pathogenesis of osteopathy and nephrolithiasis known to occur in diabetics