OBJECTIVE Complications of feeding tube placement are uncommon, but life-threatening pneumothorax has been reported in human and veterinary patients during feeding tube placement. This article describes the development of pneumothorax and the outcome associated with misplacement of nasogastric (NG) tubes in the tracheobronchial tree in 13 dogs. ANIMALS 13 dogs being treated for various medical conditions that had NG tubes placed in 4 hospitals. PROCEDURES A review was carried out of the medical records of 13 dogs that developed pneumothorax after misplacement of NG tubes between 2017 and 2022. RESULTS 14 dogs out of 4,777 (0.3%) developed pneumothorax as an adverse effect of NG tube misplacement in the tracheobronchial tree. One dog was excluded due to incomplete medical records. The feeding tube size ranged from 5F to 10F, and the most common tubes utilized were polyurethane tubes with flushing stylets. Nine out of 13 dogs developed evidence of respiratory compromise after the NG tube was placed. Eleven dogs required thoracocentesis, and 5 dogs had thoracostomy tubes placed. Five dogs suffered cardiopulmonary arrest after developing pneumothorax, with 3 of 5 undergoing cardiopulmonary resuscitation. Two out of 3 dogs that underwent cardiopulmonary resuscitation were discharged from the hospital. Five of 13 dogs were successfully discharged from the hospital, while 5 dogs died or were euthanized because of the pneumothorax. CLINICAL RELEVANCE Pneumothorax is a rare but potentially life-threatening complication of NG tube placement in dogs and may lead to death if not immediately addressed. Practitioners should be aware of this complication and be ready to perform thoracocentesis quickly if appropriate.