3-Phosphoglycerate dehydrogenase (3-PGDH) is a key enzyme involved in the serine biosynthesis pathway. It catalyzes the conversion of 3-phosphoglycerate to 3-phosphohydroxypyruvate, which is the first step in serine synthesis. 3-PGDH consists of multiple functional domains and is mainly located in the cytoplasm. The expression of this enzyme varies in different tissues and cells, participating in the regulation of amino acid metabolism, neurotransmitter synthesis, and cell proliferation. Mutations or dysregulation in the gene encoding 3-PGDH are associated with various diseases, including neurological disorders, metabolic disorders, and cancer.