Spontaneous remission of adult acute myelogenous leukaemia (AML) represents a rare event. We report a 60-year-old female patient suffering from secondary AML Ml and severe invasive pulmonary hyalohyphomycosis highly suggestive of aspergillosis. Two months after the diagnosis of leukaemia, she achieved a spontaneous remission lasting 3 months, although neither cytostatic drugs nor corticoids were administered because of a septic condition. At the time of remission, a chronic hepatitis C virus infection and a polyclonal hypergammaglobulinaemia were present, and the patient received granulocyte colony-stimulating factor once. This report represents the first documentation of a spontaneous remission in AML following invasive pulmonary hyalohyphomycosis. Possible mechanisms of this phenomenon are discussed.