Residential side air-conditioning loads come as a high-quality resource to participate in demand side response due to their sizeable total capacity, flexibility in regulation, and thermal storage properties of their environment. Adjustable capacity assessment of air-conditioning loads is the basis for orderly control of air-conditioning loads participating in demand side response. However, ignoring the differences in phase types in which the air conditioner is located during the evaluation and control process may lead to an increase in the three-phase unbalance. To avoid increasing the three-phase unbalance of residential loads during regulation and to make efficient use of the advantages of three-phase air-conditioning regulation, this paper proposes a control strategy for residential air-conditioning loads aggregation in multilayer clusters considering three-phase unbalance and three-phase load unbalance management. First, based on the equivalent thermal parameter (ETP) model, the air-conditioning loads model of a residential area containing fixed-frequency, inverter, and domestic central air conditioners was constructed. Then, this paper constructs a model for assessing the adjustable capacity of a single air-conditioning load based on users' thermal comfort, willingness, and degree of controllability. Finally, a multilayer cluster strategy for air conditioners based on three-phase, single-phase, and equivalent thermal parameters is proposed, as well as a multiple group control strategy for air-conditioning loads that considers demand side response and three-phase unbalance management. The validity of the method in this paper is verified by examples.