1. A method for the purification of the nicotinamide nucleotide-independent alcohol dehydrogenase of Pseudomonas sp. M27 is described. 2. In the analytical ultracentrifuge, the purified enzyme shows a single major component of molecular weight 146000. 3. On electrophoresis in polyacrylamide gels between pH5.0 and 9.55, it shows only one protein band and the isoelectric point appears to be between pH7.0 and 8.0. 4. Spectrographic analysis indicates no significant metal content. 5. Amino acid analysis shows an unusually small number of cysteine/cystine residues per molecule as well as about 4.1% of glucosamine. 6. The role of ammonia as enzyme activator has been investigated.