PuraStat® (3D Matrix, Tokyo, Japan) is a novel, self-assembling peptide hemostatic hydrogel that can be used endoscopically. Hemostasis can be physically obtained by covering bleeding points; however, there are no reports of how long PuraStat remains in the upper gastrointestinal tract. Herein, we report a case wherein esophagogastroduodenoscopy (EGD) was performed 2 hours after PuraStat application. A 73-year-old man underwent EGD for evaluation of lesions in the posterior wall of the stomach. A biopsy was then performed on the gastric lesions; however, massive bleeding occurred. A hemostatic clip was used to stop bleeding but failed; primary hemostasis was obtained by applying PuraStat. EGD performed 2 hours later to determine whether the patient could be discharged revealed that the white-turning PuraStat gel remained firmly in the applied area, confirming complete hemostasis. PuraStat is a hemostatic agent capable of physical hemostasis that reliably remains in the stomach even after a few hours of use and, thus, may replace some conventional hemostasis methods.