A bed device has a load measurement unit for generating a load signal a first computation unit for computing a center-of-gravity variation or load variation on the basis of the load signal a first determination unit for determining whether the computation result for the center-of-gravity variation or load variation is equal to or greater than a first threshold value a totaling unit for totaling the number of times that the computation result is determined to be equal to or greater than the first threshold value a second computation unit for multiplying the totaling results by coefficients for each time period and adding the results and a second determination unit or determining a waking or sleeping state or determining a body movement or rest state of a user on the basis of whether a computation result of the second computation unit is equal to or greater than a second threshold value.
