Gastroesophageal reflux disease (GERD) is cancerous. According to endoscopic and pathological findings, GERD can be divided into three categories: erosive esophagitis, non-erosive reflux disease, and Barrett’s esophagus, among which Barrett’s esophagus has a high probability of cancer. Long-term stimulation of esophageal mucosa by gastric contents will cause its changes, and in the process of esophageal mucosal repair, squamous epithelium is replaced by columnar epithelium, which is called Barrett’s esophagus. It is the main precancerous lesion of esophageal adenocarcinoma, leading to the appearance of tumors, such as esophageal adenocarcinoma and cardia cancer. Gastroesophageal reflux disease should be treated promptly to reduce the risk of cancer. It is recommended to seek timely medical treatment and take the next step under the guidance of your doctor.