To study the bone thickness of zygomaticoalveolar crest in adult skeletal class Ⅱ patients with different vertical facial types by cone beam CT, and to provide some guidance for the safety and initial stability of micro-implant implantation in zygomaticoalveolar crest. Methods From June 2017 to June 2019,120 adult patients with skeletal class Ⅱ (40 patientswith high angle, 40 patients with average angle and 40 patients with low angle) were selected from the Department of Orthodontics, Affiliated Stomatological Hospital of Chongqing Medical University. CBCT scan data were imported to measure the bone thickness of different coronal planes in the zygomaticoalveolar crest at H13, H15, H17 and L1-L6 at an angle of 60° with the functional plane, and the data were statistically analyzed. Results The bone thickness of zygomaticoalveolar crest was both gradually decreased from H13 to H17, and the statistical significance was significant (P <0.01). The bone thickness of zygomaticoalveolar crest was both gradually decreased from L1 to L6 level, and the statistical significance was significant (P <0.01). Comparison between high, average and low angle groups, L1-L3 was low angleaverage angle>high angle, except for B6-1 and B6-3, there was no significant difference in other measurement sites (P >0.05). Conclusion In general, the bone thickness in the zygomatic alveolar crest region of adults of skeletal class II malocclusion is gradually thinned from cranial direction and rearward.On the part of the bone thickness, the microimplants in thezygomaticoalveolar crestcan be placed forward in the selection of the implantation sites for the patients with high angle, and backward in the patients with low angle.In the clinic,we can combine the CBCT and palpation of the zygomaticoalveolar crest to improve the security and the successful rate of microimplants implantation.