Two cadmium(II) entangled frameworks, Cd(BIPA)(bpe)1.5 (1) and Cd(BIPA)(bpp)(H2O) (2), were prepared by hydrothermal reactions based on rigid 5-bromoisophthalic acid (H2BIPA) and two flexible bipyridyl ligands 1, 2-bis(4-pyridyl)ethane (bpe) and 1, 3-bis(4-pyridyl)propane (bpp). The complexes were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. Complex 1 is a rare example of a polycatenated array of 1D nanotubes, whereas complex 2 exhibits a three-dimensional twofold interpenetrating diamondoid network. The analysis results reveal that the flexibility of the bipyridyl ligands plays a significant role in the structure of the final products. Moreover, the luminescent properties of the complexes were investigated.