This study to evaluate the performance of eight diagnostic tests for HIV/AIDS infection was conducted at the National Reference Center for HIV/AIDS/STD in Lomé, Togo. The tests were as follows: Enzymum test anti HIV Combi, Enzymum tests anti-HIV1 + 2 + subtype O, Genscreen HIV 1/2, Ice 1.0.2, Vironostika HIV Uni-Form II Plus O, Genie II HIV 1/2, SFD HIV 1/2 PA and DETERMINE HIV 1/2. A total of 238 serum specimens collected consecutively between January and April 1999 were studied. They were from 161 occasional blood donors and 77 patients. New Lav-Blot I and Ii (western blot) were used as reference tests. Test sensitivity ranged from 90 to 100%. Specificity ranged from 96 to 100%. The Enzymum test anti HIV Combi used only on serum samples from blood donors demonstrated a sensitivity and specificity of 100%. Tests based on Elisa (Emzymum Combi, Enzymum HIV 1 + 2 + subtype O, Genscreen, Ice 1.0.2 and Vironostika) allowed acceptable diagnosis of HIV/AIDS as alternatives to western blot. Two of the three rapid assays tested provided acceptable results, i.e., Genie II HIV 1/2 and SFD HIV 1/2. They are suitable for screening to prevent HIV transmission by blood transfusion in areas where Elisa is unfeasible.