Osteoprotegerin (OPG)/“receptor activator of nuclear factor kappa B-ligand” (RANKL) system has an important role in the remodeling of bone through regulation of osteoclastogenesis. We aimed to detect OPG and RANKL levels, particularly in obese children in the pubertal period and to investigate whether these parameters correlate with insulin resistance in childhood. Our study included 66 obese children ranging in age from 9.1 to 16 years, and 22 non-obese children ranging in age from 10.5 to 16 years. Blood glucose, insulin, total cholesterol, HDL cholesterol, and LDL cholesterol levels were measured for all cases; HOMA-IR, Quicki index and atherogenic index were calculated. Serum OPG and RANKL levels were also measured. OPG and RANKL levels did not show any difference between obese and non-obese children (P>.05). No difference in these 2 parameters were observed among the children with and without insulin resistance (P>.05). No correlation could be established between the OPG, the HOMA-IR, Quick and atherogenic indices. Obesity and insulin resistance are believed to show their effect in the later period of life to become able to change some of the parameters.