Estrogen plays a crucial role in the development and function in reproductive physiology. Estrogens regulate cellular activity through binding to estrogen receptor α (ERα) and β (ERβ). ERα polymorphisms have been associated with changes in age at menarche, menopause onset, and fertility. The aim of this study is to investigate the relationship of ERα gene polymorphisms with central precocious puberty (CPP) in girls. Two hundred and one (201) Korean girls with idiopathic CPP were included in this study along with 100 healthy Korean female adults with pubertal maturation within normal age who served controls. Auxological and endocrine parameters were measured, and both patients and controls were genotyped for PvuII (397 T→C) and XbaI (351 A→G) polymorphisms in the ERα gene. A significantly lower incidence of the CC genotype with PvuII polymorphism were noted among CPP girls than controls (11.9% vs. 22%, P=0.021). However, the clinical parameters did not differ among the 3 genotypes. In addition, there was no significant difference in patients with the XbaI polymorphism compared to controls. The present study reveals that neither PvuII nor XbaI polymorphisms in the ERα gene are associated with onset and progression of puberty. However, further studies are needed to validate the exact function of these polymorphisms.