Management of bleeding is critical for improving patient outcomes. While various hemostatic products are used in daily practice, technical improvement is still needed. To addresses this problem, we newly developed a microneedle hemostatic sheet based on microneedle technology. We demonstrated the unique features of this microneedle hemostatic sheet, including reduced hemostatic time, biodegradable polymer composition that allows intracorporeal use without increasing infectious risk incorporation of microneedles to fix the sheet to the wound even on the left ventricular wall of a swine while beating, and a mesh structure with flexibility comparable to that of bonding surgical tape and sufficient rigidity to penetrate human aorta tissue and swine left ventricular wall. One potential application of the microneedle hemostatic sheet is intracorporeal topical hemostasis for parenchymatous organs, large vessels, and heart wall during trauma or surgery, in addition to new, widespread applications.