The nickel complex Ni(phen)(H(2)O)(3)[C(8)H(11)O(2)(COO)] has been synthesized with bicycle[2.2.1]hept-2-en-5,6-dicarboxylic acid [C(7)H(8)(COOH)(2)] by means of solvent way. It crystallizes in the triclinic space group P (1) over bar, with a=0.780 58(16) nm, b=1.1899(2) nm, c=1.214 8(2) nm, alpha=66.20 degrees(3), beta=88.28(3)degrees, gamma=86.33(3)degrees, V=1.0303(4) nm(3), D(c)=1.554 g center dot cm(-3), Z=2, F(000)=502. Final GOF=1.107, R(1)=0.0264, wR(2)=0.0702. The crystal structure shows that the nickel ion is coordinated with four oxygen atoms from one bicycle [2.2.1]-2-hepten-5,6-dicarboxylic acid molecule and three water molecules, respectively, with two nitrogen atoms from the 1,10-phenanthroline molecule, forming a distorted octahedral coordination geometry. The result of TG analysis shows that the title complex was stable under 210.0 degrees C. CCDC: 741933.