IntroductionRacial and environmental differences in communities leading cause of differences in serum lipids. It can be said this study aimed in assessing percentile curves of serum lipid profile in 6 to18 year- old of students at Birjand, east of Iran.Methods and MaterialsThe present cross-sectional study was done on 4168 students of Birjand aged 6-18 years. They were classified into three age groups (6-10) and (15-18) and (11-14) years. The 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of lipids [Cholesterol, Low density lipoprotein (LDL), High density lipoprotein (HDL) and triglycerides] were determined by sex for different age groups.ResultThe 5th, 10th, 25th, 50th, 75th, 90th and 95th percentiles for cholesterol, LDL, HDL, and Triglycerides (TG) were: (114,123, 138, 157, 176, 197, 210; 54, 59, 71, 86, 102, 119, 131; 33, 36, 41, 48, 56, 64, 68 and 43, 49, 61, 78, 103, 138, 164) respectively.ConclusionPercentiles of lipid in kids of Birjand were different in comparison with reference percentiles of the U.S and also Tehran. Triglycerides and HDL in children and adolescents were higher and lower, respectively than the Americans. This could be due to racial differences and environmental factors such as nutrition and sedentary life style. This should be considered in interpretation of normal and abnormal values and determination of dyslipidemia in children and adolescents.