Lipoamide dehydrogenase, which is a common component of alpha-keto acid dehydrogenase complexes, has been highly purified from yeast (Saccharomyces cerevisiae) to reveal its structure at higher resolution. New crystals obtained by a desalting method exhibited diffraction beyond 2.5 A resolution. The cell dimensions are a = 97.1, b = 158.7, and c = 67.9 A, and the space group is P2(1)2(1)2(1). There is a dimeric enzyme in the asymmetric unit. The crystal structure was solved by means of the molecular-replacement technique and refined in a preliminary manner.