Waste biomass from food systems are  considered as a renewable source to produce bioactive greener platform chemicals. Thus, significant emphasis has been given for the development of modern and novel technologies for waste biomass recycling, which have several characteristics such as being fast, clean, sustainable, cost-effective, and environmentally friendly. Phenolic compounds such as Ferulic acid, vanillin, Sinapic acid, Cinnamic acids and platform chemicals such as 2,3 Butane Diol, 1,3 Propane Diol, lactic acid, succinic acid, citric acid, acetic acids, high value microbial protein etc. are the part of the waste biomass having wide range of applications in various food, pharmaceuticals, cosmetic sectors. Circular bioeconomy concept holds importance as it can offer for generation of various bioactive phenolics form sustainable resources through implication of biotechnology-based approaches. Hence, the bioeconomy is important in the waste utilization sector, and the transition from waste to resources can be achieved by reframing waste biomass and by-products as valuable phenolic compounds increasing waste reduction, and integrating waste biomass more broadly in the sustainable development goal (SDG) agenda. To promote the circular (bio)economy approach in the waste biomass sector, the proposed special issue focuses on complete solutions for the efficient use of waste biomass as a raw material to produce greener phenolic compounds used as phytochemicals, antioxidants, and value-added products. Papers related to the different microbial conversion technologies, chemical and bioprocess design, environmental technologies, greener platform chemicals, waste valorisation, and novel biocatalysts for waste utilization towards value addition will be covered in this special issue. By integrated biorefinery solution for waste biomass, the developed circular bioeconomy can definitely open a road map towards sustainable development through complete resource utilization.