Background Total thoracoscopic segmentectomy (TTS) is a technically challenging procedure in children but results in more parenchyma preservation, better pain control, better cosmetic results, and a shorter hospital stay. However, definitive data describing the learning curve of TTS has yet to be obtained. Here, we review the safety and efficiency of our initial experiences with pediatric TTS and evaluate our learning curve. Methods This was a retrospective study of all pediatric patients undergoing TTS between December 2016 and January 2020. Pediatric patients who underwent TTS were included, while those undergoing lobectomy or wedge resection were excluded. Results One hundred and twelve patients were retrospectively analyzed to evaluate the learning curve and were divided chronologically into three phases, the ascending phase (A), plateau phase (B) and descending phase (C), through cumulative summation (CUSUM) of the operative time (OT). Phases A, B, and C comprised 28, 51, and 33 cases, respectively. OT decreased significantly from phases A to B (p < 0.001) and from phase B to C (p = 0.076). No significant differences were observed in the demographic factors among the three phases. The conversion rate was zero, and the complication rate was 0.9%. Differences in technical parameters, such as length of stay and chest tube duration, were statistically insignificant between phases A and B or B and C. There were no mortalities. Conclusion CUSUMOT indicates that the learning curve of at least 79 cases is required for TTS in our institute. We emphasize that the learning curve should be cautiously interpreted because many factors in different institutions may influence the exact parabola and actual learning curve. [GRAPHICS] .