Reevaluation of the deferral from voluntary blood donation by men who have sex with men (MSM) is being discussed in several countries, motivated by the need to ensure a blood supply free from transfusion-transmissible infections (e.g., HIV, syphilis). Policies being considered include: permanent exclusion for any male-male sexual encounter, temporary deferral (3 months, 12 months, 5 years) from the last encounter, or specifying behaviors that differentiate MSM at high risk from those at low risk. Current Brazilian regulations defer MSM from blood donation for 12-months after the last male-male sexual encounter. Broad epidemiological evidence indicates that many MSM are at increased risk for HIV in the present era, and few data exist to distinguish which men are likely to be in the immunological window for detection of these infections. A multicenter study developed in Brazil demonstrated that the history of male-male sex was the most strongly associated with being an HIV-positive blood donor. Meanwhile, the blanket deferral of MSM from blood donation has generated considerable controversy. Rejection of the deferral policies stems in part from perspectives defending human rights, promoting equality and citizenship, and alleging bias and discrimination. The objective of this report is to discuss the current situation of blood donation among MSM in Brazil. We highlight the lack of evidence for a true risk profile for male-male sex in the context of blood donation upon which to base sound policy. We recommend research to establish effective and acceptable criteria for blood donation by MSM and other blood donors.