Abstract: Tree nutrient acquisition, immune defense activation, and vegetative growth are essential and intricately linked components for ensuring long-term survival in highly dynamic and competitive forest ecosystems. Understanding the intrinsic regulatory mechanisms governing these evolutionary trade-offs, especially within the complex biological framework of long-lived perennial woody plants, can lead to significantly enhanced ecological adaptability of forest ecosystems under adverse conditions. Herein, we review and present a comprehensive framework for understanding the sophisticated multi-layer defense architecture of trees and its deep functional coupling with advanced nutrient sensing and transport systems. We begin by detailing how the continuous biological availability and stable absorption of nutrients go far beyond merely maintaining basic physiological and metabolic activities. Previous studies have demonstrated that these nutritional components serve as crucial regulatory hubs that influence the magnitude and timing of immune responses during pathogen infection. Chronic nutrient deficiency can fundamentally weaken host resistance by inducing extensive metabolic reprogramming and systemic hormonal imbalances. Research has then explored the intricate interactions where specific nutrient transport proteins have evolved into complex dual-function sensors. During active pathogen invasion, these unique proteins trigger systemic acquired resistance by dynamically reconfiguring internal nutrient allocation networks and prioritizing resource distribution toward active defense zones. Furthermore, evolutionary insights are provided by comparing the divergence between woody species and traditional herbaceous model plants. This highlights how the highly lignified secondary xylem structures and prolonged perennial growth strategies of trees drive pathogens to develop highly specialized infection mechanisms, alongside the corresponding immune adaptations established by woody hosts. Additionally, previous research has deciphered the core roles of key molecular signaling hubs, encompassing the evolutionary expansion of immune receptor families and the complex downstream cascades of transport protein modules. By synthesizing recent scientific breakthroughs in multidimensional information integration—including environmental temperature perception, complex rhizosphere microbial interactions, and long-distance metabolic signaling—an overall regulatory network model is presented wherein internal nutrient status acts as the central hub balancing active growth and stress immunity. This review not only provides a framework to project our present and future understanding of the synergistic regulatory mechanisms between nutrient growth and immunity but also offers a solid theoretical foundation for future disease resistance molecular breeding, precise nutrient management strategies, and the efficient utilization of global forestry resources.