The white button mushroom (Agaricus bisporus), a widely consumed vegan food, typically has a short shelf-life of 1–3 days under ambient storage conditions due to its high moisture content and susceptibility to microbial spoilage. This study aims to enhance its postharvest longevity through a natural, functionalized coating technique utilizing aloe vera gel in combination with essential oils, selected based on optimized in vitro antifungal efficacy. The essential oils of neroli and palmarosa demonstrated significant antifungal activity at a concentration of 9 μL per Petri plate by effectively inhibiting the radial mycelial growth of isolated postharvest fungal pathogens Trichoderma lentinulae and Rhizopus arrhizus. Among various tested formulations, a coating composed of pure aloe vera gel blended with palmarosa essential oil at 600 μL/L concentration yielded the most favorable results. This treatment significantly preserved physiochemical parameters, including controlled weight loss, firmness, and higher total phenolic content, all indicative of delayed senescence and better retention of quality. Furthermore, sensory evaluations and antioxidant activity assays confirmed the acceptability and functional benefits of the treated white button mushrooms. The shelf-life of the white button mushrooms increased to a period of 16 days under the storage conditions of 4±1℃ and 85-90% RH. Overall, this eco-friendly and bioactive coating system offers a promising alternative to synthetic preservatives, providing a natural means of extending the shelf-life and maintaining the postharvest quality of white button mushrooms.