There is provided a bedding item selection system capable of selecting a bedding item easy to improve the state of sleep. A bedding item selection system S1 includes: a plurality of test bedding items T whose physical property including firmness is different from one another; a deep sleep rate calculation unit 1f which calculates a deep sleep rate of a user P based on biological information measured and recorded; a suitable physical property recognition unit 1h which recognize a suitable physical property based on the physical property of a test bedding item T high in deep sleep rate of the user P; and a bedding item selection unit 1j which selects, from a plurality of selectable bedding items M, a bedding item based on the suitable physical property.