AbstractMallory−Weiss syndrome (MWS) is a common cause of gastroesophageal bleeding. Vomiting increases intra‐abdominal and intra‐esophageal pressures, causing hyperextension of the esophagogastric junction and laceration. Most affected patients respond well to conservative treatment; however, those with active bleeding require endoscopic intervention. Upon contacting blood, PuraStat gels and coats the bleeding point to achieve hemostasis. PuraStat is reportedly effective for non‐variceal bleeding and bleeding associated with endoscopic procedures. However, there have been no reports on the use of PuraStat in MWS. Here we report a case in which PuraStat was useful for achieving hemostasis in a patient with MWS and difficult‐to‐achieve hemostasis. The patient was a 67‐year‐old man who had undergone coronary artery bypass grafting 1 month earlier and was taking an antithrombotic drug. He visited our hospital with bloody vomiting and melena in the evening and was diagnosed with upper gastrointestinal bleeding for which he underwent endoscopy. MWS with active bleeding was observed in the lower esophagus extending to the esophagogastric junction. We treated the patient with clipping; however, the oozing did not stop because of the large laceration. We applied PuraStat to the bleeding site and confirmed that the oozing had resolved; therefore, the procedure was terminated. The endoscope was reinserted the next day and confirmed the hemostasis. The patient was discharged without further deterioration. In patients with MWS with active bleeding, endoscopic hemostasis is commonly achieved using clips or endoscopic band ligation. However, PuraStat can achieve complete hemostasis when these techniques fail.