d-Glucaric acid (GA) is an important platform chemical with wide applications in material, food, and pharmaceutical industries. GA production by separation and purification from plants is not applicable at large scale. Instead, there are three ways to produce GA: chemical, enzymatic, and microbial synthesis. This chapter introduces the research progresses in chemical, enzymatic, and microbial synthesis of GA, especially the latter two featuring the concept of green biomanufacturing. The key rate-limiting factors, both for enzymatic and microbial production of GA from sugars, are the supply of myo-inositol and the catalytical performance of myo-inositol oxygenase (MIOX). These are pivotal engineering targets to improve the production titers, rates, and yields of GA. In the broader context of global warming and carbon neutrality, cheaper renewables such as lignocellulose and even CO2 could be used as abundant carbon sources to produce GA in a more environmentally friendly manner. At last, we envision that the future of GA biomanufacturing and its industrial applications is bright, encouraged by the entrepreneurial successes exemplified by Kalion, Inc.