The organic load of dairy waste, mainly by-products like whey, buttermilk, and casein sludge, is a major environmental matter. The present investigation into sustainable waste management and resource reclamation options becomes pertinent in light of rising concern over untreated dairy effluents. Green valorization of dairy leftover and protein recovery through environmentally friendly approaches is the subject matter of this chapter. It also covers the necessary steps in the protein extraction process, including advanced methods such as enzymatic hydrolysis and ultrafiltration, as well as pretreatment, which comprises filtration and pH adjustment, among others. Other green valorization strategies are explored with an exceptional focus on its compensations over more conventional methods such as efficiency and sustainability, among others. This section further examines recovered proteins’ process of purification methods, such as chromatography and dialysis. In addition to that, nutrient and functional assessment is made as well as reviewing environmental benefits coupled with the sound economic feasibility involved in scaling such procedures for application at industrial sites. It reports challenges and hurdles in presenting cases of valorization of dairy industry effluent waste to date. Last but not least, the potential for future development and the prospect of emerging technologies that can enhance the sustainability and efficiency of dairy waste valorization are discussed. This chapter then delves into innovative and maintainable approaches to protein recovery in the food and nutraceutical industries, thus providing a comprehensive overview of the topic of green valorization of dairy waste.