Objectives We aimed to investigate the effectiveness of the Korean medical critical pathway (CP) in treating childhood anorexia. Methods In total, 21 patients who met the criteria and agreed to provide information were assigned to the CP group, while 24 patients who met the criteria, agreed to provide information, but disagreed with CP application were assigned to the non-CP group. Demographic, clinical, and economic indices were compared between the two groups. Clinical indices before and after treatment were also compared between the two groups. Results In the CP group, height, weight, body mass index (BMI), BMI percentile, and food approach (FAP) increased significantly after treatment, and numeric rating scale (NRS) and food avoidance (FAV) scores decreased significantly. In the non-CP group, height, weight, weight percentile, BMI, BMI percentile, and FAP increased significantly, whereas NRS and FAV decreased significantly after treatment. Compared to the non-CP group, CP application increased FAP and decreased FAV, medical expenses per consultation, and the total treatment period. Conclusions The application of the Korean medical critical pathway for childhood anorexia is an effective cure system that decreases overall medical expenses with good-quality treatment by means of the standardization of medical practices.