Constructed from 2,5-bis(4-pyridyl) thiazolo[5,4-d]thiazole (Py₂TTz), sulfate anions and metal ions Cd(II), a new 3D luminescent metal-organic framework (LMOF) with good water stability is synthesized under solvothermal condition. [Cd(Py₂TTz)(SO₄)]_n (Py₂TTz = 2,5-bis(4-pyridyl) thiazolo[5,4-d]thiazole). It crystallizes in tetragonal space group P4_2₁m with a = 6.830(3), b = 6.830(3), c = 17.676(12) Å, V = 824.5(8) ų, Z = 4, M_r = 504.83, D_c = 2.033 g·cm^-3, F(000) = 496, GOOF = 1.088, the final R = 0.0434 and wR = 0.0948 for 6301 reflections with I > 2σ(I). Upon excitation at 370 nm, the emission peak of the compound appears at 455 nm, which has a slight redshift compared to the free ligand Py₂TTz. The compound has potential to be a luminescence sensing material.