A mobile robot includes at least two first reflection parts, each of the at least two first reflection parts having a first reflection surface on a side surface thereof, the first reflection surface being configured to reflect electromagnetic waves. For each of the at least two first reflection parts: a cross-sectional shape obtained by being cut in a first direction perpendicular to a reference axis is symmetrical and continuous with respect to points passing through the reference axis, the first direction being parallel to a top surface of the first reflection part or a bottom surface of the first reflection part; and a reflection surface angle defined by the points passing through the reference axis and both ends of the first reflection surface is 90 degrees or more to 360 degrees or less when the first reflection part is viewed along the reference axis.