Background　Lithium　carbonate　(Li2CO3)　is　widely　used　in　the　treatment　of　clinical-affective　psychosis.　Exposure　to　Li2CO3　during　pregnancy　increases　the　risk　of　neural　tube　defects　(NTDs)　in　offspring,　which　are　severe　birth　defects　of　the　central　nervous　system.　The　mechanism　of　Li2CO3-induced　NTDs　remains　unclear.　Methods　C57BL/6　mice　were　injected　with　different　doses　of　Li2CO3　intraperitoneally　on　gestational　day　7.5　(GD7.5),　and　embryos　collected　at　GD11.5　and　GD13.5.　The　mechanisms　of　Li2CO3　exposure-induced　NTDs　were　determined　utilizing　immunohistochemistry,　western　blotting,　EdU　imaging,　enzymatic　method,　gas　chromatography-mass　spectrometry　(GC-MS),　ELISA　and　HE　staining.　Results　The　NTDs　incidence　was　33.7%　following　Li2CO3　exposure.　Neuroepithelial　cell　proliferation　and　phosphohistone　H3　level　were　significantly　increased　in　NTDs　embryos,　compared　with　control　group　(P　＜　0.01),　while　the　expressing　levels　of　p53　and　caspase-3　were　significantly　decreased.　IMPase　and　GSK-3　beta　activity　was　inhibited　in　Li2CO3-treated　maternal　and　embryonic　neural　tissues　(P　＜　0.01　and　P　＜　0.05,　respectively),　along　with　decreased　levels　of　inositol　and　metabolites,　compared　with　control　groups　(P　＜　0.01).　Conclusions　Lithium-induced　NTDs　model　in　C57BL/6　mice　was　established.　Enhanced　cell　proliferation　and　decreased　apoptosis　following　lithium　exposure　were　closely　associated　with　the　impairment　of　inositol　biosynthesis,　which　may　contribute　to　lithium-induced　NTDs.　Impact　Impairment　of　inositol　biosynthesis　has　an　important　role　in　lithium　exposure-induced　NTDs　in　mice　model.　Lithium-induced　NTDs　model　on　C57BL/6　mice　was　established.　Based　on　this　NTDs　model,　lithium-induced　impairment　of　inositol　biosynthesis　resulted　in　the　imbalance　between　cell　proliferation　and　apoptosis,　which　may　contribute　to　lithium-induced　NTDs.　Providing　evidence　to　further　understand　the　molecular　mechanisms　of　lithium-induced　NTDs　and　enhancing　its　primary　prevention.