A new water-stable europium MOF, (Me₂NH₂)[Eu(abtc)(phen)]·2H₂O (1), has been synthesized from Eu(NO₃)₃·6H₂O with 1,10-phenanthroline (phen) and 3,3′,5,5′-azobenzenetetracarboxylic acid (H₄abtc) ligands under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction analysis, IR, TGA and PXRD. It crystallizes in monoclinic system, C2/c space group, with a = 16.278(3), b = 14.261(3), c = 27.936(5) Å, b = 103.464(3)°, V = 6307(2) ų, Z = 8, C₃₀H₂₆EuN₅O₁₀, M_r = 768.5, D_c = 1.543 g/cm³, F(000) = 2912, m(MoKa) = 2.044 mm^‒1, R = 0.0315 and wR = 0.0663. In the structure of 1, the EuO₇N₂ polyhedra are assembled into a 2D layer with rhombic windows and these layers are further condensed to form a 3D framework. It can be used as selective and sensitive fluorescence sensors capable of detecting diethyl ether vapor.