The invention relates to a blood cannula for discharging blood into a vessel, in particular aortic cannula for discharging blood into an aortic arch during heart-bypass surgery, comprising a tubular body (1), the tubular body having a straight part at the proximal end (2) and a bent part at the distal end (3) leading into an outlet opening (5), wherein the distal end (3), in particular the bent part has an increasing cross section in the direction of blood flow (B).
