By utilizing nicotinic acid as a co-ligand, two new azido-bridged cobalt(II) complexes with the formulae [Co₂(N₃)(nic)₂Cl(H₂O)]_n (1) and [Co(N₃)(nic)]_n (2) (nic = nicotinate) have been synthesized under solvothermal condition and structurally characterized. Complex 1 exhibits a rare three-dimensional (3D) Kagomé topology with [Co4] units as connecting nodes. Complex 2 is also a 3D structure which contains 1D Co^II–μ-1,1-azido chains as rod-shaped SBUs. Magnetic data analysis shows that ferromagnetic coupling intra-[Co4]-cluster and antiferromagnetic interaction inter-[Co4]-cluster exists in complex 1, while complex 2 exhibits metamagnetism with a critical field of 5.5 kOe.