Ensuring food for the continuously increasing global population is one of the most challenging aspects for scientists and researchers around the globe. To meet the growing demand for food, agricultural expansion is necessary. However, traditional agriculture is crucial to meet the nutritional requirements for humanity as well as to make countries self-sufficient in food production. Conventional farming techniques depend on the widespread use of synthetic fertilizers and pesticides for plant nutrition and disease pest management. The use of such chemical inputs in different crop fields is popular to farmers for plant growth, crop production, and quality, but also for farmers’ income. However, these chemical inputs pose a considerable threat to the natural environment by contaminating water, air, and soil. Eco-friendly approaches, such as organic farming and bio-fertilizers, are gaining popularity as a more sustainable alternative to conventional agriculture. Organic farming helps in reducing dependence on artificial plant protection inputs in field crop production. Bio-fertilizers are a type of fertilizer that uses microorganisms that promote plant growth and are referred to as biofertilizers or microbial inoculants. Biofertilizers are getting priority in world agriculture due to simple production technology and low installation cost. The purpose of this review is to summarize the current knowledge on biofertilizers and their potential for sustainable agriculture.