Provided is a blood filter that resists deterioration in properties as a result of electron beam sterilization treatment performed before or during use as a blood filter, has durability, dimensional stability, and chemical resistance at excellent levels, also has biocompatibility, and resists deterioration in properties even upon the electron beam sterilization treatment. The blood filter according to the present invention includes a nonwoven fabric made of PEEK fibers. Preferably, the blood filter according to the present invention has an average pore size of 3 to 280 µm and has a porosity of 15% to 70%; and the PEEK fibers have an average fiber diameter of 10 µm or less.