Human T-lymphotropic viruses type I (HTLV-I) and type II (HTLV-II) infections have been related to lymphoproliferative disorders and subacute neurological diseases. Screening blood donors for specific HTLV-I/II antibody has been implemented in Japan, United States, and recently in France. Should be it recommended in Spain?Antibodies to HTLV-I/II were investigated in sera from 7,884 individuals living in Spain. They were classified in four major groups: 1) subjects at high-risk for retrovirus infection, as drug addicts, homosexuals, and polytransfused individuals (n = 4,740), 2) patients suffering HTLV-like symptoms (n = 760), 3) immigrants from or travellers to endemic areas (n = 1,427), and 4) blood donors (n = 957).Eighteen (0.22%) subjects were HTLV-I positive and 11 (0.12%) were classified as HTLV-II reactive. Five (71.5%) of 7 immigrants or travelers to endemic areas reacting against HTLV were typed as HTLV-I. Six (60%) of 10 drug addicts HTLV-reactive were typed as HTLV-II carriers.Both HTLV-I and HTLV-II infections are present in Spain, although in a low rate and mostly restricted to drug addicts (HTLV-II), and people coming from endemic regions (HTLV-I). All tested blood donors were negative. In this view, HTLV-I/II screening in Spanish blood banks seems to be non urgent, although alternative strategies should be considered.