Biofertilizers have emerged as promising tools for supporting sustainable and organic agriculture by improving nutrient availability, enhancing soil fertility, and promoting plant growth through natural biological processes. Increasing concerns regarding the environmental impacts of synthetic fertilizers have intensified interest in biological alternatives capable of maintaining agricultural productivity while reducing ecological pressures. This review examines the role of biofertilizers in sustainable agricultural systems, focusing on their classification, mechanisms of action, and contributions to soil health and environmental sustainability. The analysis highlights the ability of biofertilizers to improve nutrient cycling, stimulate beneficial microbial activity, enhance soil biodiversity, and reduce dependence on chemical fertilizers. Their application may contribute to water quality protection, pollution reduction, and the preservation of ecosystem services essential for long-term agricultural productivity. In addition, the review discusses the challenges associated with biofertilizer use, including variable field performance, formulation stability, regulatory constraints, and farmer adoption. Recent advances in microbial biotechnology, microbiome research, and precision agriculture have created new opportunities for improving biofertilizer effectiveness and expanding their agricultural applications. Overall, biofertilizers represent an important component of environmentally responsible farming systems and may play a significant role in the transition toward more sustainable and resilient agricultural practices.