Serum levels of angiotension converting enzyme (ACE) are elevated in many patients who suffer from sarcoidosis. Few studies have correlated ACE levels at diagnosis with the radiographic stage of the disease. The present authors reviewed the charts of all patients who had the diagnosis of sarcoidosis made between 1990 and 1995, and correlated ACE level at diagnosis with radiographic stage. Only patients with biopsy-proven sarcoid were included. One hundred and sixteen cases were identified, and complete data were available for 104 individuals. Serum ACE levels were increased in approximately 63·5% of the study population. The relationships between both stage and ACE level, and stage and percentage of individuals with elevated ACE levels within that stage were not statistically significant (P>0·05). This large, retrospective study of patients with histologic evidence of sarcoidosis demonstrated no association between serum ACE level and radiographic stage.