A panel of eight tests was used to study 200 cases of acute brucellosis, 200 patients negative for brucella as a control group and 200 apparently healthy individuals as a second control group. The best diagnostic test was the rose Bengal test using an imported reagent (BioMérieux, France) and 2 local reagents. This test was improved from being a screening test to be a titrable one. The best two tests used together were the tube agglutination test with Coomb-like test. The indirect fluorescent antibody test had no advantages over the use of other tests. The 2-mercaptoethanol test and C-reactive protein test were useful in checking the brucellosis activity. Normal numbers of E-rosette forming cells and inefficient neutrophils in phagocytosis were found in peripheral blood during acute brucellosis.