Nanocellulose, a promising bionanomaterial, is gradually being recognized for its potential in environmental remediation due to its abundance, cost-effectiveness, eco-friendliness, high surface area, non-toxicity, and exceptional mechanical properties. This chapter provides a comprehensive overview of various types of nanocellulose, their properties, and their application as a photocatalyst in environmental remediation. It also discusses recent advancements in nanocellulose-based photocatalysts for pollutant degradation, highlighting their effectiveness in breaking down organic and inorganic contaminants under light irradiation. The potential integration of nanocellulose with other materials to enhance its photocatalytic performance is also explored. Finally, challenges and future directions in this field are addressed, including the need to scale up production and improve photocatalytic performance for practical applications in wastewater treatment. This chapter provides insights into the state-of-the-art developments and prospects of nanocellulose-based photocatalysts for sustainable and efficient wastewater treatment solutions.