To investigate the clinical effect of tongue removable orthodontic appliance in the early orthodontic treatment of anterior dental crossbite during mixed dentition period. Methods From May 2019 to May 2022, 80 children with anterior dental crossbite correction during mixed dentition period admitted to Xianghe County People's Hospital were selected as the research objects. They were divided into control group and study group by random number table method, with 40 children in each group. The control group was treated with conventional orthodontic scheme, and the study group was treated with tongue removable orthodontic appliance. The clinical efficacy, correction of cephalometric index and completion time of treatment were compared between the two groups. Results The total effective rate of treatment in the study group was 92.50%, which was higher than 75.00% in the control group, and the difference was statistically significant (P <0.05). After treatment, the upper alveolar seat angle, mandibular plane angle, upper and lower alveolar seat angle and maxillary central incisor and NA connection angle in the study group were higher than those in the control group, and the differences were statistically significant (P <0.05). The lower alveolar seat angle, mandibular central incisor and NB connection angle in the study group were lower than those in the control group, and the differences were statistically significant (P <0.05). The completion time of corrective treatment in the study group was shorter than that in the control group, and the difference was statistically significant (P <0.05). Conclusion The tongue removable orthodontic appliance can effectively improve the cephalometric indicators of children with anterior crossbite correction during the mixed dentition period, and its therapeutic effect is ideal and worthy of clinical application.