Mycorrhizal symbiosis, or a beneficial partnership between plant roots and fungus, is critical for boosting crop nutrition and soil fertility. Mycorrhizal fungi, a varied collection of organisms from the phylum Glomeromycotina, develop extensive hyphal networks in the soil matrix. These networks considerably boost the plant’s ability to absorb important nutrients such as micronutrients, phosphate, and nitrogen. Different mycorrhizal fungus species, including ectomycorrhizae, ericoid mycorrhizae, and arbuscular mycorrhizae, provide distinctive advantages to various species of plants and habitats. In exchange, the plant provides the fungus with carbohydrates. In addition to improving the physiological and chemical features of the soil, this mutualistic relationship promotes microbial diversity, avoids soil erosion, speeds up the decomposition of organic materials, and stimulates the manufacture of plant growth hormones. Because of all these factors, soil fertility has grown. Mycorrhizae also bolster crops’ defenses against soil-borne pathogens, improve nutrient absorption, and increase their resistance to abiotic stresses. Increased yields and better nutritional value are thus advantageous to crops. Taking everything into account, these mycorrhizal activities are crucial for boosting soil fertility and are a practical strategy in modern agricultural systems and crop yields. The remainder of this chapter gives a summary of the molecular principles behind the symbiotic relationship between mycorrhizal fungi and discusses strategies to enhance crop nutrition and soil fertility for sustainable agricultural operations.