Ecological thresholds have demonstrated significant utility in early warning and controlling ecosystem degradation, but their potential application in proactive territorial ecological restoration remains underexplored. To investigate the functional mechanisms of ecological thresholds in proactive restoration, this study systematically examined their theoretical foundations and logical connections with ecosystem succession, thereby establishing the applicability in ecological recovery processes. Building upon these foundations, this study developed an action framework for territorial ecological restoration mediated by ecological thresholds, proposing an integrated technical system and a comprehensive management paradigm encompassing “issue identification - proactive intervention - efficacy monitoring - adaptive cycling - resilience management”. Through engineering practice perspectives, this study elucidates the distinctive role of ecological thresholds in proactive intervention compared with passive-guided restoration, while clarifying threshold effects and underlying mechanisms during territorial ecological rehabilitation. Quantitative cases analyze on degraded grassland restoration further explores threshold-informed intervention techniques and their implementation potential. By incorporating ecological thresholds into proactive restoration strategies, this study provides novel perspectives for optimizing whole-process management in integrated restoration of mountain-river-forest-farmland-lake-grassland-desert ecosystems, particularly regarding objective setting and effectiveness evaluation.