An increased (p < 0.001) frequency of bronchial hyperreactivity (BHR) was found in sarcoidosis patients as compared with healthy volunteers. The patients had more mast cells (p < 0.001) and tryptase (p < 0.001) in their bronchoalveolar lavage fluid, but there were no differences between BHR-positive and BHR-negative patients. Furthermore, the bronchoalveolar lavage fluid concentrations of macrophages, lymphocytes, and of the soluble components albumin, fibronectin, and vitronectin were also elevated in the sarcoidosis patients, indicating an ongoing inflammation in the airways and/or in the interstitium. We observed no significant differences in the parameters when the sarcoidosis patients were subdivided into BHR, clinical activity, or chest X-ray stages. Our findings may indicate a multifactorial background to the hyperreactivity.