A coil unit may include a coil in a substantially rectangular frame shape; and a coil holding member. A thickness direction of the coil may be perpendicular to a long side of the coil and a short side of the coil. An outer peripheral face of the coil holding member may include an abutting face in a flat shape with which the coil is abutted. A protruded part may be formed formed so as to protrude from the abutting face to an outer side of the coil holding member. A protruded part end face parallel to the abutting face may be formed on a tip end side of the protruded part in a protruding direction of the protruded part. A distance between the abutting face and the protruded part end face may be equal to a thickness of the coil.