BACKGROUND: Post-pneumonectomy bronchopleural fistulas (BPFs) are associated with high morbidity and mortality. Currently, since the management of BPFs is difficult to assess, the best therapeutic approach is prevention. Our objective was to evaluate the effects of adipose-derived stem cells (ASCs) on the healing of the bronchial stump in an experimental animal model. METHODS: Left pneumonectomy was performed in 37 Sprague-Dawley rats. Animals were randomly assigned to a control group (n = 13), an ASC group (n = 12), and an ASC plus Tissucol(®) group (ASCT) (n = 12). The ASCs and ASCTs were locally administered at the bronchial stump after surgical pneumonectomy. Animals were killed at 10 and 20 days. We analyzed histological changes and changes in the expression of relevant genes involved in wound repair in the bronchial stump. RESULTS: Two control animals, one animal from the ASC group, and one from the ASCT group died from early BPF. All the remaining animals had an adequate postoperative outcome. ASCs and ASCTs significantly decreased the necrosis and ulcerations of the bronchial stump at 10 and 20 days. ASCs significantly decreased mRNA expression of Igf1 at 10 days and Igf1, Tgfb1, Vegfa, and Col2a1 at 20 days, whereas there was increased expression of Agc1 and Col2a1 at 10 days and Sox6 at 20 days. CONCLUSIONS: Our findings indicate that local ASCs protected the bronchial stump after pneumonectomy and induced local changes in gene expression related to their protective action. These results could lead to a potential new therapeutic modality for the prevention of BPF.