A　series　of　lanthanide　binuclear　complexes,　[Ln(2)(L)(6)(H2O)(4)]center　dot　2H(2)O　(Ln=Sm(III),　Gd(III),　Er(III),　Yb(III),　HL=4-quinolineacarboxylic　acid,　were　synthesized　by　reactions　of　corresponding　rare　earth　salts　with　4-quinolineacarboxylic　acid　at　room　temperature　and　were　characterized　by　elemental　analysis,　IR　spectroscopy,　and　single-crystal　X-ray　diffraction.　X-ray　diffraction　analyses　showed　that　they　exhibited　the　same　binuclear　architecture　and　crystallized　in　monoclinic　system　and　P2(1)/c　space　group.　In　four　complexes,　each　metal　center　adopted　nine-coordinated　mode　coordinated　by　nine　O　atoms　from　two　H2O　molecules　and　three　carboxyls　of　three　ligands,　and　HL　showed　three　different　coordination　modes.　The　variable-temperature　magnetic　susceptibility　showed　that　complex　[Gd-2(L)(6)(H2O)(4)]center　dot　2H(2)O　performed　very　weak　antiferromagnetic　property　at　low　temperature　and　exchange　was　almost　paramagnetic　at　high　temperature.　Complexes　[Er-2(L)(6)(H2O)(4)]center　dot　2H(2)O　and　[Yb-2(L)(6)(H2O)(4)]center　dot　2H(2)O　performed　dominating　antiferromagnetic　coupling.