The transition to a circular economy (CE) shift from the linear model by reducing waste, reusing resources, and fostering sustainable growth. Biomass waste, particularly lignocellulosic biomass from agricultural residues, forestry by-products, and municipal waste, is a key renewable resource for this shift. This chapter explores how biomass waste can reduce greenhouse gas emissions, improve waste management, and create economic opportunities, especially in developing regions. Biomass waste plays a crucial role in the CE by adhering to the principles of reducing, reusing, and recycling materials. Through technologies like anaerobic digestion, pyrolysis, and gasification, biomass waste can be converted into bioenergy, biochar, and valuable bioproducts. These closed-loop systems promote sustainable development, addressing global challenges such as climate change and resource depletion. The chapter also discusses the technological, regulatory, and economic factors influencing biomass waste utilization, emphasizing the need for supportive policies and investment. Case studies demonstrate successful applications of biomass waste in various sectors, highlighting collaboration among governments, industries, and communities. Challenges such as technological limitations and economic feasibility are explored, along with future prospects for scaling up biomass waste utilization.