The bed device has load measurement means for generating a load signal first computation means for computing a center-of-gravity variation or load variation on the basis of the load signal first determination means 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 totaling means for totaling the number of times that the computation result is determine to be equal to or greater than the first threshold value second computation means for multiplying the totaling results by coefficients for each time period and adding the results and second determination means for 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 means is equal to or greater than a second threshold value. Movement of a user can thereby be monitored by using load information of a bed unit, and the waking state or body movement state of the bed user can be detected with high precision.
