The invention discloses a cardiovascular surgical arterio-venous fistula hemostasis device. The cardiovascular surgical arterio-venous fistula hemostasis device comprises an adjusting seat and a bandage, wherein the section of the adjusting seat is trapezoid; lugs are symmetrically arranged on two slopes of the adjusting seat; rotation shafts are arranged between the lugs; vertical plates are arranged on two sides of the top surface of the adjusting seat; mutually-milled roll shafts are arranged between the two vertical plates; the bottom end of the bandage is fixed on a rotation shaft on one side; the other end of the bandage bypasses a rotation shaft on the other side and penetrates between the mutually-milled roll shafts. According to the cardiovascular surgical arterio-venous fistula hemostasis device, the bandage is tightened by the mutually-milled roll shafts, so that the adjusting seat generates downward pressure; the pressure is used for pressing a hemostasis part of a patient for hemostasis; a pressure sensor inserted into the bottom surface of the adjusting seat is used for detecting the pressure between the adjusting seat and a patient pressing part and displaying the pressure on a display screen of a touch screen type controller, so that the medical accidents caused by improper pressure intensity can be effectively avoided.