PROBLEM TO BE SOLVED: To provide an unconventional sleep disorder-improving agent.SOLUTION: A composition for improving sleep disorder or the sleep disorder-improving agent includes glycine as an effective component.COPYRIGHT: (C)2013,JPO&INPIT【課題】従来にない熟眠障害改善剤の提供。【解決手段】グリシンを有効成分として含有する熟眠障害改善のための組成物、又は熟眠障害改善剤。【選択図】なし