Disclosed is a mobile robot including a body, a rotating plate rotatably installed on the body and having a lower surface where a mop portion is attached, and an attachment guider installed on the lower surface of the rotating plate to guide an attachment position of the mop portion. The attachment guider includes a guide rim and a plurality of elastic pieces. The guide rim is disposed to surround a rotation axis of the rotating plate. The plurality of elastic pieces extend from the guide rim in a direction toward the rotation axis, have a free end protruding to a lower side or downward than the guide rim, and are spaced apart from each other along a circumference of the guide rim.