The increasing demand for sustainable and efficient technologies for wastewater treatment has led to the exploration of biomass-derived quantum catalysts. An environmentally suitable starting point for producing sophisticated catalytic materials is biomass, an abundant and renewable resource. The processes of converting biomass into quantum catalysts, such as pyrolysis, chemical activation, hydrothermal carbonisation, and microwave-assisted synthesis, are thoroughly covered in this chapter. These catalysts’ structural and functional properties, such as their high surface area, photocatalytic activity, and functional group diversity, make them highly effective for degrading organic pollutants, removing heavy metals, and eliminating pathogenic microorganisms from wastewater. This chapter also discusses real-world applications, challenges, and future directions for scaling up this innovative approach. By integrating green chemistry principles and nanotechnology, biomass-derived quantum catalysts offer a sustainable solution to global wastewater treatment challenges, contributing to environmental protection and resource conservation.