The case of a 36-year-old male with renal tubular acidosis and atypical hypoparathyroidism is reported. He came to our clinic complaining of pain in his left thigh. Upon X-ray examination, subtrochanteric fracture of left femur, malunited fracture of left tibia, osteosclerosis of spine and short tubular bone and basal ganglia calcification were seen. Upon biochemical examination, hypokalemia, hypocalcemia, hyperchloremia and metabolic acidosis were found. From the findings of the renal function test, NH4 Cl loading test and bicarbonate loading test, this case was diagnosed as proximal renal tubular acidosis. The findings of the i-PTH and Ellsworth-Howard test suggested that this case might have been suffering from atypicalhypoparathyroidism. Acidosis was hardly corrected with oral administration of bulky sodium bicarbonate (30-50g/day) but hypocalcemia was almost corrected with Vitamine D.