We report two patients with Warthin's tumor who were also infected with Mycobacterium tuberculosis. Case 1 was a 75-year-old woman with Warthin's tumor and multiple small epithelioid granulomas with caseous necrosis involving the submandibular gland. This patient died of tuberculous meningitis 4 months after biopsy. Case 2 was a 78-year-old man with a 10-year history of a parotid mass which had enlarged rapidly over 2 months. Surgical excision revealed Warthin's tumor and epithelioid granulomas involving the left parotid gland. DNA extracted from paraffin sections was amplified by nested polymerase chain reaction (PCR) with primer sets for the mycobacterial 65-KDa antigen gene. Restriction enzyme digestion of the PCR products could differentiate Mycobacterium tuberculosis from other mycobacteria in both cases. Although the histogenesis of lymphoid components of Warthin's tumor is controversial, the frequent prevalence of inflammation or necrosis and our present findings suggest these components have a similar behavior to regional lymph nodes.