Abstract: A surgical instrument for one-handed preparation of an anastomosis in minimally invasive surgery has, from the distal end to the proximal end, an interchangeable insertion head (1), a staple holder (30) with U-shaped staples and with a circular groove with thread placed in it, an ejector unit, an gently bendable, adjustable and fixable joint (6), an annular knife retained on the ejector unit, a hollow-cylindrical holder part that is axially displaceable in the annular knife and has a number of elastically resilient, radially pivotable gripper and holder arms (20), a circular-cylindrical shaft (7) mounted on the proximal end of the joint (6), an adjusting and fixing device (8) with a hand wheel (80) mounted on the proximal end of the hollow shaft, and a handle (9) with a toggle lever mechanism (90, 93) pivotably connected to it. (FIG. 1).