PURPOSE: To easily finish bed-making of a bed in a short time by a method wherein inflatable bags are arranged on a bedstead and along both edges of the bedstead so that the a mattress is lifted in one side at a time to fold the hems of a sheet under the mattress.

CONSTITUTION: When a bed-making of a bed 1 is carried out, a used sheet is removed first and a new sheet 14 is spread over the bed 1. In this state, two inflatable bags 15 are in a flattened state and the rear face of a mattress 13 is in close contact with a top face 12a of a bedstead 12. Then, an air delivery pipe 20 of a treadle air pump 19 is connected to an air feed pipe 16 of one of the inflatable bags 15 and the treadle air pump 19 is pressed by the foot to feed air into the inflatable body 15. The inflatable bag 15 is inflated and the mattress 13 is lifted on one side, causing a gap to be produced between the rear face of the mattress 13 and the top face 12a of the bedstead 12. Then, the hem of the sheet 14 spread over the mattress 13 is folded between the mattress 13 and the top face 12a of the bedstead 12. Thus bed-making is completed.