The use of biological fertilizers has grown significantly during the last two decades. Their massive use is a result of the high demand of raw material for food production and supply, worldwide. They act as traditional chemical fertilizers' substitutes, have a good performance in harvests, help to the growth of sane fruits that resist plagues and are easy to apply. Besides, essential nutrients contained in biological fertilizers have physical-chemical properties that are beneficial to the soil, helping to increase productivity in the global agricultural sector. In this article a revision to the main current techniques for the biological fertilization is made, and an outlook to its future potential for sustainable agricultural development is shown.