A barrel polishing apparatus has a barrel tank. The barrel tank includes a cylindrical fixed tank having a center axis and a rotary disk provided to cover a bottom portion of the fixed tank and rotatable about the center axis. The barrel polishing apparatus further includes a tilting mechanism. The tilting mechanism has a tilting shaft extending in a horizontal direction to tilt the barrel tank around the tilting shaft. The tilting shaft is disposed closer to the upper edge of the fixed tank than a centroidal line extending parallel to the tilting shaft and passing through the center of gravity of the barrel tank when viewed from a direction parallel to an extending direction of the tilting shaft.