The most widely used method for treatment of secondary hyperparathyroidism(SH) in CAPD patients has been the administration of calcitriol by oral route. In this study, we compared the efficacy and safety of daily low dose calcitriol therapy with those of intermittent high dose pulse therapy. The study group consisted of 38 patients undergoing CAPD with serum intact PTH level of more than 200pg/ mL. Twenty patients were randomly administered daily low dose calcitriol(0.25μg/day for 1 month followed by 0.5μg daily dose for the next 3 mon-ths) while 18 patients were given intermittent pulse therapy(0.5μg-0.5μg-0.75μg 3 times a week for 1 month, increased to 1.0μg-1.25μg-1.25μg 3 times a week for the next 3 months). Thirty five patients completed the study : 17 on daily oral calcitriol (M: F=0.7:1, mean age=47.3±10.6 years, mean duration of CAPD=48.9±41.1 months), and 18 on oral pulse calcitriol(M: F=1.6: 1, mean age=41.5±12.7 years, mean duration of CAPD=49.2±41.6 months). The baseline serum levels of calcium, phosphorus, i-PTH, alkaline phosphatase, and total CO₂were not different be- tween daily and pulse group(9.5±0.8 vs 9.3±0.9mg/ dL, 5.8±1.3 vs 5.1±1.2mg/dL, 443.1±162.5 vs 546±385.9pg/mL, 91.8±47.7 vs 108.9±66.5IU/L, 23.7±1.9 vs 25.5±2.0mEq/L, p>0.05, respectively). The i-PTH level decreased significantly in daily calcitriol group after 1 month(332.8±214.8pg/mL, p<0.01), and at final evaluation(180.4±254.8pg/mL, p<0.01). In pulse calcitriol group, i-PTH level also decreased signi-ficantly to 400,4±225.8pg/mL(p<0.05), 89.4±122.6 pg/mL(p<0.01), respectively. The rate of decline in i-PTH level from baseline were similar(daily=25.4±22.7 vs pulse=19.5±12.6%decline/month, p>0.05). The serum calcium increased similarly in both groups after treatment(daily=10.6±0.8 vs pulse=l0.1±1.0mg/ dL, p>0.05). Hypercalcemia(>11.0mg/dL) was rarely observed in all patients(daily=5, pulse=8 episodes). In conclusion, both daily and pulse calcitriol therapy were similarly effective and safe in control of SH.