Objective To evaluate the clinical efficacy and safety of the 3-month formulation of triptorelin (triptorelin pamoate) in the treatment of idiopathic central precocious puberty (ICPP) in children. Methods A retrospective analysis was conducted of 49 children with ICPP treated with the 3-month formulation of triptorelin at Xiangya Hospital, Central South University, from May 2023 to September 2025. All patients received at least one injection and completed a 3-month follow-up. The numbers of patients who subsequently completed 6-, 9-, and 12-month follow-ups were 42, 26, and 11, respectively. Sex hormone levels, growth and development, and the differences between bone age and chronological age (ΔBA-CA) were assessed at 3, 6, 9, and 12 months after treatment initiation. Results At diagnosis, after the gonadotropin-releasing hormone agonist stimulation test, the peak luteinizing hormone (LH) level was (15.6±5.8) IU/L, the peak follicle-stimulating hormone (FSH) level was (8.5±3.9) IU/L, and the peak LH/FSH ratio was 1.9±0.9. After 3 months of treatment, 92% of the children achieved a peak LH <3 IU/L, all children had a peak LH/FSH ratio <0.6, and estradiol or testosterone decreased to prepubertal levels; this suppression was maintained through 12 months without rebound. In girls, uterine length was significantly reduced from baseline at 3, 6, 9, and 12 months (P<0.0125). In boys, testicular volume was significantly reduced from baseline at each follow-up (P<0.0125). At 3, 6, 9, and 12 months, ΔBA-CA was significantly decreased compared with baseline in all children (P<0.0125). The incidence of adverse reactions during treatment was low, no treatment discontinuations due to adverse events occurred, and overall tolerability was good. Conclusions The 3-month formulation of triptorelin effectively suppresses the hypothalamic-pituitary-gonadal axis and delays bone age progression in children with ICPP, providing the potential to improve adult height, with a favorable safety profile.