Background: To determine daily calcium, Vitamin D intake and serum biochemical findings of rickets in adolescent girls.Methods: Atotal of 414 healthy adolescent student girls aged 11-15 years were evaluated from various areas of Tehran, Iran with different socioeconomic status. A randomized, cross-sectional, prospective and descriptive study was undertaken for calculation of daily calcium, phosphorus intake and vitamin D acquirement by sunlight exposure by seven day recall record questionnaire. Serum 25-hydroxyvitamin D, parathyroid hormone, calcium, phosphorus and alkaline-phosphatase levels were measured. The serum abnormal biochemical findings of girls were divided as follows: normal or low calcium with raised alkaline phosphatase, group I; normal or low calcium with raised alkaline phosphatase, normal or raised parathyroid hormone, low 25- hydroxyvitamin D, group II and low phosphorus and 25-hydroxyvitamin D with raised parathyroid hormone, group III.Results: A total of 44 (10.62%) girls of 414 had abnormal biochemical findings, of these 29 (7%) were in group I, 9 (2.17%) in group 11, and 6 (1.45%) in group III.The mean daily calcium intake and vitamin D acquirement by sunlight exposure and dietary intake were 360.85±350.50 mg and 119.2±52.91 Urespectively. All girls had inadequate dietary calcium and vitamin D intake. All had less than 40 minutes sun exposure per day.Conclusion: This survey demonstrated that abnormal biochemical findings of rickets can occur even in sunny climates and are is caused by two factors, inadequate calcium intake as the major factor and vitamin D deficiency as a minor factor.