To provide a sleeping environment control system which grasps the number of body motion after bedding of a user, facilitates sleeping of the user timely after the bedding by using a cheap load sensor and prevents a body temperature of the user from being excessively taken after the stopping of sweating.

A sleeping environment control system includes: a bed 4 equipped with legs 6; a load meter 11 which is disposed under the leg 6 and detects a load applied to the legs 6; an air conditioner which conditions air in a bed room; a temperature deciding part which determines a sleeping state of the user on the basis of the variations of the load detected by the load meter 11 and decides a preset temperature of an air conditioner 13 on the basis of the sleeping state of the user; and a control substrate 12 which controls the air conditioner 13 such that the temperature of the bed room gets to the preset temperature decided by the temperature deciding part.