Planar honeycomb-like coordination network {[Ni(cyclam)](3)[W(CN)(8)](2)}(n) (cyclam = 1,4,8,11-tetraazacyclotetradecane) was obtained in the self-assembly reaction of [Ni(cyclam)](2+) and [W(CN)](8)(3-). Its structure is characterized by void channels along the a axis. The compound shows reversible water adsorption in the temperature range of 25-40 degrees C with the formation of {[Ni-(cyclam)](3)[W(CN)(8)](2)}n center dot 16nH(2)O, accompanied by single-crystal-to-single-crystal transformation. The structural transformation significantly changes the character of intraplane magnetic exchange interactions.