P. marneffei infection was diagnosed in 127 patients, 42.5% by both blood and skin lesion culture, 29.1% by blood culture alone, and 28.3% by skin lesion culture alone. The average age was 32 years (range 21-50); the majority was male (75.6%), and 81.9% came from provinces outside of Hanoi in northern Vietnam. The reported route of HIV infection was intravenous drug use (IDU) (37.0%), commercial sex (29.9%), husband to wife (15.7%), combination of IDU and commercial sex (7.9%) and unknown (9.0%). 29.9% had been on antiretroviral therapy (ART) prior to the diagnosis of penicilliosis; the mean duration of ART was 10.8 weeks (SD 18.4).