Alkaline phosphatase from bovine synovial fluid was purified 2300-fold. A molecular weight of 72,300 was determined from sucrose density gradient studies. The following monoesters were hydrolyzed by the enzyme: P-glycerophosphate, galactosamine 6-phosphate, glucosamice 6-phosphate, glucose 6-phosphate, o-phospho-L-serine, o-carboxyphenyl phosphate, phenyl phosphate, and p-nitrophenyl phosphate....