A fatal case of pulmonary berylliosis in a 42 year old male is described. The patient was exposed to beryllium while working in a chemical plant over a 9 year period, and presented two years after ceasing such employment. The berylliosis was diagnosed on open lung biopsy in 1971. The patient was commenced on steriod therapy at that time. He suffered progressive dyspnoea from severe restrictive lung disease over the next 14 years. A chest X-ray of June 1985 revealed a lesion in the left upper lobe suggestive of a mycetoma. Before any therapy could be instituted he suffered a massive haemoptysis and died. Post-mortem examination revealed two large mycetomata in the right and left upper lobes. Parenchymal histology showed evidence of chronic inflammation with non-caseating granulomata and the cavity wall showed localized invasion by Aspergillus fumigatus. It is possible that the long term steroid therapy with multiple boosters of treatment may have contributed to the development of the mycetoma. This is the first case report known to the authors of a fatal aspergilloma in association with chronic berylliosis treated with steroids.