Objective: To compare the clinical effects of Invisalign® mandibular advancement (MA) appliance and Twin-block appliance on skeletal class II malocclusion. Methods: We selected 22 children who were treated for skeletal Class II malocclusion with an average of (12.02±1.61) years old. They were treated with Twin-block appliance (12 cases, Twin-block group) and Invisalign® MA (10 cases, MA group). The cephalometrics were taken before and after the treatment, and the cephalometric data of 2 groups were analyzed. Results: Compared with MA group, L1-MP angle and SN-MP angle increase in Twin-block group, which have significant difference (P<0.05). The increase of L1-NB angle, L1-NB distance and L6-MP distance in the Twin-block group are more than that in the MA group and have significant difference (P<0.05). L1-MP distance decreases in MA group but not in Twin-block group, and there was significant difference between the 2 groups (P<0.05). Conclusion: Both MA and Twin-block can promote mandibular growth and improve lateral profile. If we don’t want to proline the lower incisors or increase the angle of mandibular plane, MA is a better choice for patients. Twin-block appliance is more suitable for patients with a lower angel of the mandibular plane.