This paper describes the first detection of Brucella sp. antibodies in seals from the Antarctic territory. Sixteen antarctic fur seal (Arctocephalus gazella) and one Weddell seal (Leptonychotes weddellii) sera were tested by the Rose Bengal test (RBT), complement fixation test (CFT), immunodiffusion (AGID) and c-ELISA. Antibodies against Brucella sp. were detected with the RBT, the CFT and the c-ELISA in six of the seventeen samples involving the two animal species. It is concluded that a Brucella sp. described as affecting marine mammals in the Northern hemisphere could be also present in the Antarctic territory.