A cleaning brush includes bristles that have ends which come into contact with an object to be cleaned having irregularities on a surface thereof, and a brush base on which the bristles are arranged. The bristles include first bristles and second bristles. The first bristles have a thickness too great to reach bottoms of recessed portions of the irregularities on the surface of the object to be cleaned. The second bristles have a thickness small enough to reach the bottoms of the recessed portions of the irregularities on the surface of the object to be cleaned.