The increasing need for sustainable agricultural practices due to the overuse of chemical fertilizers has prompted interest in microalgae as biofertilizers. This review investigates the potential of microalgae as biofertilizers and phycoremediators within sustainable agroecosystems, addressing both soil fertility and wastewater management. Microalgae provide a dual benefit by absorbing excess nutrients and contaminants from wastewater, generating nutrient-rich biomass that can replace chemical fertilizers and support plant growth. Implementation strategies include cultivating microalgae in wastewater to offset production costs, using closed photobioreactor systems to enhance growth efficiency, and applying microalgal biomass directly to soil or crops. Additionally, microalgae extracts provide essential bioactive compounds, such as phytohormones and amino acids, that enhance plant growth and resilience. While microalgae offer an eco-friendly solution for nutrient recycling and crop productivity, challenges in scalability, production cost, and regulatory frameworks hinder widespread adoption. This review highlights the potential pathways and technological advancements necessary for integrating microalgae into sustainable agriculture, emphasizing the need for interdisciplinary collaboration and innovative approaches to overcome these barriers. Ultimately, microalgae biofertilizers represent a promising approach to reducing environmental impact and advancing sustainable farming practices.