A novel coordination polymer nickel 1,3,5-benzenetricarboxylate (TMA) Ni3(H2O)6(TMA)3-(TMA)23-·2H2O with two-dimensional porous structure was synthesized and characterized. It crystallizes in the hexagonal system, space group P6522, with a=1.665 2(10) nm, c=2.045 4(11) nm, V=4.912(5) nm3, Z=6, Dc=1.916 g·cm-3, μ(Mo K)=0.181 8 mm-1, F(000)=2 892. The final R1=0.066 4, wR2=0.175 6 for 2 710 observed reflections [I>2σ(I)] out of 2 904 unique reflections . This coordination polymer reveals not only two-dimensional porous structure but also particular magnetic properties. CCDC: 274177.