An incubator comprising a mattress tray (16) and a plurality of baby guards (23 to 26) surrounding a vicinity of an outer periphery of the mattress tray (16), wherein: a first baby guard (23) from out of the plurality of baby guards (23 to 26) includes a grommet (42); the first baby guard (23) is detachably attached to a first attachment location installed at a vicinity of the outer periphery of the mattress tray (16); a second baby guard (24) from out of the plurality of baby guards (23 to 26) is detachably attached to a second attachment location installed at a vicinity of the outer periphery of the mattress tray (16); and the first baby guard (23) is detachable from the first attachment location and attachable to the second attachment location, and the second baby guard (24) is detachable from the second attachment location and attachable to the first attachment location.