Two new Mn(II) coordination polymers, namely, [Mn(Haip) 2 (H 2 O) 2 ] (1), and [Mn 2 (aip) 2 (bpy)]·3H 2 O (2) were obtained under hydrothermal conditions (aip=5-aminoisophthalate; bpy=2, 2′-bipyridine). Compound 1 features a 1D loop-like chain structure, and complex 2 possesses an interesting (3, 5)-connected 2-nodal 3D architecture with the Schläfli symbol of (4.6 2 )(4.6 7 .8 2 ), which is constructed from helical chains. Coordination modes of H 2 aip molecules and coligands have significant effect on the structures of the resulting complexes. Moreover, variable-temperature magnetic susceptibility measurement of complex 2 exhibits antiferromagnetic interactions between nearest Mn(II) ions with J=−0.88(5)cm −1 and g=2.04(3).