Objective:Premature thelarche is defined as breast enlargement in females (younger than eight years) without other signs of secondary gender character development. Although it is common in the first two years of life, it can be seen in any age group before the age of eight. In this study, girls who presented to pediatric endocrinology outpatient clinic due to early breast development were retrospectively analyzed.Method:Patient data were analyzed retrospectively between 01.01.2011 and 31.12.2011 (one year) from pediatric endocrinology outpatient clinic files. Patients under two years of age and cases with precocious puberty were excluded from the study.Results:Twenty-six patients with the mean age of 6.87±1.07 years were included in the study. Premature pubarche was also present in 12 (46%) of the cases. Height and weight standard deviations were 0.92±1 and 1.09±0.75, respectively. The standard deviations of body mass index were over 1 in 61.5% of the cases (16 cases). There was no correlation between the age of onset of thelarche and the age of first permanent tooth eruption and birth weight.Conclusion: Although the etiology of premature thelarche is still unclear, there is increasing evidence that it may be associated with an increase in body fat mass.