The contamination of aqueous resources with organic and inorganic pollutants poses a critical threat to human survival, ecosystems, and environmental health. Conventional wastewater treatment methods such as adsorption, membrane filtration, and chemical precipitation rely on nanomaterials (e.g., polymers, carbon-based, metallic, and metal oxide nanomaterials) but face limitations including toxicity, high costs, energy inefficiency, secondary pollution, and inadequate efficacy. Microbial-driven synthesis of nanoparticles (NPs) has emerged as a sustainable and innovative alternative, offering enhanced efficiency and environmental compatibility. This review systematically explores the transformative potential of microbial nano-biotechnology in water remediation, highlighting its superiority over traditional approaches. By synthesizing cutting-edge advancements, this chapter provides a roadmap for developing green, scalable, and cost-effective strategies to address global water contamination challenges, thereby catalyzing future research in sustainable wastewater treatment technologies.