Abstract: Agricultural production frequently encounters extreme weather conditions, including droughts, floods, elevated temperatures, and frost, which significantly affects crop yields. In arid and semi-arid regions, inadequate irrigation and declining groundwater levels often result in diminished crop productivity. Furthermore, challenges such as soil salinization, acidification, and elevated concentrations of heavy metals and organic pollutants present substantial risks to soil fertility and human health. Enhancing plant resilience to abiotic stressors and addressing environmental pollution are critical for advancing sustainable agricultural practices. Poly-γ-glutamic acid (γ-PGA), a natural polymeric compound produced by microorganisms, is recognized for its water-absorbing, chelating, and biodegradable properties. It holds potential applications in agriculture as a soil water-retention agent, fertilizer synergist, plant growth enhancer, and soil remediation agent. This article provided a comprehensive review of the applications of γ-PGA in environments affected by abiotic stressors, such as drought, salinization, heavy metals, and acidification, as well as its role in the remediation of organic pollutants. Additionally, it offered insights into future research directions, aimed at enhancing the understanding of γ-PGA’s mechanisms and broadening its potential applications.