PROBLEM TO BE SOLVED: To provide an FK506 derivative which has no immunosuppressive activity but maintains nerve regeneration activity, a preparing method thereof, and a pharmaceutical composition comprising the same for preventing or treating nervous system diseases.SOLUTION: A pharmaceutical composition for preventing or treating nervous system diseases, contains one FK506 derivative selected from the group consisting of 31-O-demethyl-FK506, 9-deoxo-31-O-demethyl FK506, or 9-deoxo-prolyl-FK506 represented by formula 2.SELECTED DRAWING: Figure 1【課題】免疫抑制活性がなく、神経再生活性は維持されるFK506誘導体、その製造方法、それを含む神経系疾患の予防または治療用医薬組成物の提供。【解決手段】31-O-デメチル-FK506、9-デオキソ-31-O-デメチルFK506、または下記式2で示される9-デオキソ-プロリル-FK506からなる群から選択されるいずれか一つのFK506誘導体を含む神経系疾患の予防または治療用医薬組成物。【選択図】図1