The laboratory methods for the diagnosis of bovine brucellosis used today in Belgium are reviewed. Certain differences in test procedures used in different laboratories are noted. They are inventoried and standardized to enhance the eradication program. The serological tests and the isolation and biotyping of Brucella abortus are described and the results of the biotyping tests carried out in the National Institute of Veterinary Research in 1989 and 1990 are presented.