Endophytic fungi are organisms that live in plant tissues and contribute to improved resistance to diseases, tolerance to environmental stresses, and accelerated plant growth. The molecular intermediates they produce also inhibit the emergence of shoots on the stem itself, so the use of natural biopesticides can replace synthetic chemical insecticide and herbicide compounds from an environmentally friendly point of view, but is not cost-effective. Therefore, higher productivity is required. They can also improve plant nutrient uptake, plant growth, and agricultural yields. Based on these general data, applications are being developed for biological control of diseases caused by Fusarium weevils in sugarcane fields. Endophytic fungi lead to a more stratified energy intake in these improved ecosystems and support a richer population of herbivores. Although difficult to quantify, biodiversity has a very real impact on plant health and yield. Another approach to plant protection using biotechnology is using endophytes. This chapter provides an view of the understanding work in recent years on the use of endophytic fungi for biological control of agricultural pests.