This book offers a comprehensive and up-to-date overview of the escalating global challenge of microplastic pollution and highlights cutting-edge nanomaterial-based strategies for its efficient removal. It begins by examining the sources, pathways, and ecological consequences of microplastic contamination, emphasizing its growing threat to freshwater and marine ecosystems. Moving beyond the problem, the book explores how nanomaterials provide innovative, sustainable, and high-performance solutions for microplastic remediation. The book covers the synthesis and surface modification of nanomaterials, the development of adsorption and filtration systems, and advanced degradation mechanisms, including photocatalytic and enzymatic approaches. It also presents real-world applications of nanomaterials in diverse environmental settings—freshwater, wastewater, and marine systems—alongside a critical discussion of implementation challenges such as scalability, cost, and environmental safety. It also focuses on regulatory considerations, risk assessment, and emerging research directions, outlining future perspectives for sustainable nanotechnology-driven pollution control. It is a valuable resource for researchers, academicians, environmental engineers, policymakers, and professionals in nanoscience, environmental chemistry, and sustainable materials, offering novel pathways toward mitigating the adverse impacts of microplastics and safeguarding global water systems.