The trinuclear NiII cluster [Ni3(bpca)2(bpy)2(H2O)4](NO3)4·H2O (1) (bpca– = anion of bis(2-pyridylcarbonyl)amine, bpy = 2, 2′-bipyridine) was isolated. Single crystal X-ray diffraction analysis showed that three crystallographically independent NiII ions are located in a six-coordinate distorted octahedral environment, bridged by the organic spacer bpca–. The crystal lattice is stabilized by hydrogen bonds, which are linking the Ni3 cations and NO3– anions into a three-dimensional framework. Variable-temperature magnetic susceptibility for complex 1 in the range 2–300 K indicates the presence of weak antiferromagnetic interactions in the Ni3 unit with J = –0.67 cm–1.