Experimental infections of white-tailed deer (Odocoileus virginianus) with Brucella suis biovar 4 were evaluated over a period of 6 wk. Five adult male hand-raised white-tailed deer were inoculated with 1 × 10⁷ colony forming units of B. suis biovar 4 in the conjunctiva and serologically evaluated over 6 wk by the card test (CARD), rivanol test (RIV), serum agglutination test (SAT), complement fixation test (CFT), particle concentration fluorescence immunoassay (PCFIA), and competitive enzyme linked immunosorbent assay (c-ELISA), as routinely used for bovine samples. Six weeks postinoculation the animals were euthanized and cultured for B. suis biovar 4. One deer became serologically positive 4 wk post-inoculation on CFT, CARD, PCFIA, and c-ELISA. At 6 wk postinoculation, CFT was positive in four infected deer, CARD was positive in three deer; RIV, SAT, and PCFIA was positive in two deer; and cELISA was positive in one deer. Only the CFT was 100% sensitive. At necropsy B. suis biovar 4 was isolated from four of five deer, and representative colonies were biologically similar to the challenge organism.