A new Cd‐MOF containing the nucleobase adenine and multicarboxylates, Cd2(tdc)2(1H‐ade)2(H2O) (H2tdc = 2,5‐thiophene carboxylic acid, 1H‐ade = adenine), was synthesized successfully under hydrothermal condition and characterized by single‐crystal X‐ray diffraction, infrared spectrum, thermogravimetric analysis and photoluminescence. The two crystallographically unsymmetrical Cd atoms are bridged by 2,5‐tdc ligands with (κ1‐κ1)‐(κ1)‐μ3 and (κ1–κ1)–μ2 modes into two dimensional extended layers, which are further pillared with the neutral ade molecules to form a 3D frameworks stabilized by extensive π···π interactions between imidazole‐, pyrimidine‐ and thiophene‐rings. Inspection of the structure reveals that the architecture can be simplified as a 3,4,5‐ connected networks with a Schläfli symbol of (62·8)(42·63·8)(42·65·83). The photochemical property shows that the luminescent emission can be significantly quenched by aromatic azo compounds. The quenching effect coefficient (Ksv) for bis(4‐imidazol‐1‐yl‐phenyl)diazene is determined to be 4.1 × 104 m–1, indicating the title compound as a potential fluorescent sensing materials.