A new Mn(Ⅱ) coordination polymer {[Mn(timb)2(H2O)2]·(Cl)2·(H2O)2}n(1,timb = 1,3,5-tris-(imidazol-1-ylmethyl)benzene) has been synthesized and characterized by elemental analysis,IR,TG and single-crystal X-ray diffraction.The title compound crystallizes in the triclinic system,space group P1 with a=9.0774(13),b=9.8720(15),c=11.4898(16)A,α=93.378(3),β= 95.471(3),γ=101.101(3)°,V=1002.6(3)A^3,Mr=834.67,Dc=1.382 g/cm^3,μ(MoKα)=0.517mm^-1,F(000)=435,GOF=0.986,Z=1,the final R=0.0506 and wR=0.1139 for 3517 observed reflections I〉2σ(I).It consists of one-dimensional double stranded chains formed through bridging bidentate timb ligands,and these chains are further connected to yield a 3D supramolecular framework by hydrogen bonding interactions and π…π stacking interactions.