Abstract: The present disclosure refers to a blood pump as defined in claim 1 comprising:—a pump housing with a cylindrical piston chamber;—an axially and rotatably slidable free floating piston centrally positioned within the cylindrical piston chamber thereby dividing the cylindrical piston chamber into a left chamber and a right chamber, wherein the left chamber and right chamber each include an inlet and outlet transversely arranged to and communicating with the left chamber, respectively right chamber;—a linear motor unit configured to generate an electromagnetically driven translational motion of the piston along the longitudinal axis of the piston chamber alternately between a first end position and a second end position; and—at least one rotary motor unit configured to generate an electromagnetically driven rotary motion of the piston around the longitudinal axis during the translational motion of the piston between the first end position and the second end position.