Abstract: The present invention relates to an apparatus for analyzing a sleep structure according to non-restrictive weight detection. The apparatus includes load cells one installed in the predetermined locations of a bed and configured to detect the weight of a target person; low-pass filters for outputting low-pass filtered signals that belong to the outputs of the load cells; high-pass filters for outputting high-pass filtered signals that belong to the outputs of the load cells; a multiplexer for selecting any one from among the outputs of the low-pass filters and the high-pass filters; a controller configured to detect information about the target person's sleep from the low-pass filtered signals and the high-pass filtered signals, which belong to the outputs of the high-pass filters and the low-pass filters, respectively, and are input through the multiplexer, and determine the target person's sleeping pattern; and a display unit for displaying determination results of the controller.