The decision-making process concerning the maintenance of equipment significantly impacts the safety and reliability of the aeroengine system. A cyber-aeroengine system (CAS) integrates intricate aeroengine components with a cyber decision-making space based on the communication network, thereby facilitating computational support for forecasting the health status of the aeroengine system. Within the cyber realm, we introduce a novel approach termed the graph spatio-temporal attention recurrent network with phase-lag index (PLI-GSTARN) to assess the degradation states of aeroengine systems. This method constructs a spatio-temporal graph based on sensor signal correlations and information reachability across distributed sensors within the physical equipment. Subsequently, the proposed framework employs a graph attention network to capture spatial features and a long short-term memory (LSTM) layer equipped with an attention mechanism to capture temporal features inherent in the constructed graph. Ultimately, this methodology is applied to cyber–physical systems within aircraft engines to manage remaining health life and diagnose faults, yielding commendable outcomes.