Two zinc coordination polymers, [Zn(H(2)dhtp)(2,2'-bpy)-(H2O)] (1) and [Zn(H(2)dhtp)(2,2'-bpy)] (2) (H(4)dhtP: 2,5-dihydroxyterephthalic acid), have been simultaneously synthesized from a one-pot reaction system. Pure phase of 1 could be obtained by varying the ratio of Zn(II) salt/H(4)dhtp, while that of 2 could not. A reversible structural transformation between 1 and 2 was observed by heating and immersing in mother liquid, and their photoluminescent properties were also studied.