Eleven alpine ibex (Capra ibex) and 27 chamois (Rupicapra rupicapra) from Gran Paradiso National Park (Italy) were examined in March 1996. A 7-yr-old ibex buck had thick-walled carpal joints and enlargement of the right testicle characterized by necrosis and fibrosis. Microscopically, testicular lesions were characterized by large areas of necrosis, fibrosis with irregular aggregates of macrophages and lymphocytes, and scattered foci of suppuration. Specimens of the carpal bursae and testicle were cultured in serum dextrose agar and serum dextrose antibiotic plates. A Gram-negative coccobacillus was isolated from the testicle and subsequently identified as Brucella melitensis biotype 2. This is the first recognized case of brucellosis in alpine ibex.