Pulmonary haemorrhage as a manifestation of leptospirosis is rarely diagnosed in developed countries. Five patients with proven leptospirosis associated with severe pulmonary haemorrhage presented to one hospital in Far North Queensland between January 1994 and June 1997. Four required admission to the intensive care unit and one patient died. Pulmonary haemorrhage is an uncommon but severe complication of leptospirosis and may be a source of diagnostic confusion in tropical areas of Australia.