The title complex {[Ni(TCB)2/2(Him)2(H2O)2]· 6H2O}n(where TCB = 1,2,4,5 benzentetracarboxylic anion, Him=imidazole) has been synthesized in aqueous solution. The crystal structure has been determined by single crystal X ray diffraction method. It crystallizes in the triclinic system, space group (# 2) with a=1.0661(4)nm,b=1.1175(3)nm,c=1.0062(4)nm,α =94.03(3)° ,β = 110.81(3)° ,γ =114.71(2)° ,V=0.9837(7)nm3,Z=1,F(000)=478,DC=1.553g· cm- 3,F.W.=920.11,u=10.41cm- 1,R=0.040,RW=0.051.In this compound, one of the nickel atom is coordinated by two oxygen atoms from TCB, two oxygen atoms from two water molecules and two nitrogen atoms from two imidazole molecules in a trans fashion to complete an octahedron; whereas the other is ligated by four nitrogen atoms from four imidazole molecules to form a planar square geometry.