Abiotic stressors that pose a danger to global agricultural output include drought, salt, severe temperatures, and nutrient deficits. Utilizing endophytic fungi’s potential provides a creative and long-term way to lessen these difficulties. To colonize their host plants’ tissues without causing damage, endophytic fungi form symbiotic partnerships with them. Through a variety of processes, such as enhanced nutrient absorption, phytohormone regulation, the creation of metabolites that alleviate stress, and the stimulation of antioxidant defenses, they significantly contribute to the improvement of plant resistance to abiotic stressors. Furthermore, endophytes enhance plants’ resistance to harsh environments by modifying the upregulation of genes under stress conditions. The investigation of fungal endophytes, including their genetic modification and application in bioformulations to increase agricultural yield, has been made possible by recent developments in biotechnology. In addition to discussing their useful applications in agriculture, this review highlights the many ways that endophytic fungi help plants under abiotic stress and look at potential future integrations of endophyte-based methods into sustainable farming practices.