Two new two-dimensional (2D) heterometal coordination polymers [Cu2M(tzdc)(2)(H2O)(2)]center dot 2H(2)O [M = Fe2+ (1) or Mn2+ (2); tzdc(3-) = 1,2,3-triazole-4,5-dicarboxylate] were assembled by using the tzdc(3-), Cu2+, and Fe2+/Mn2+ ions. Single-crystal X-ray analysis reveals that the two compounds consist of mixed-spin microporous Kagome layers, which are packed into three-dimensional structures by hydrogen bonding and interlayer weak Cu center dot center dot center dot O interactions. When heated, they can release in a stepwise manner the uncoordinated and coordinated water molecules to produce dehydrated phases (1' and 2'), respectively, which are stable up to similar to 300 degrees C. The structures of 1' and 2' were determined by powder X-ray diffraction analysis, which reveals a change in the coordination sphere of Fe2+/Mn2+ ions from an octahedron to an elongated 4+2 form, and a microporous-to-nonporous structural transformation involving intralayer wrinkling and interlayer superimposition. When the dehydrated samples are exposed to air, they can return to the hydrated phases quickly by adsorption of water molecules. Accordingly, a reversible change in magnetism between the ferrimagnetic character of the hydrated samples and the suppressed ferrimagnetic character of the dehydrated samples was found in this reversible dehydration and rehydration. These facts indicate these 2D heterometal coordination polymers are unique flexible 2D dynamic magnetic materials.