AbstractA Cupro‐8‐thioqinoline coordination polymer, [CuI(C9H6NS)]n, was synthesized by methano‐thermal reaction of CuCl and 8,8′‐dithiodiquinoline (dtdq) in a molar ratio of 2:1 at 160°C for 7 d. X‐Ray single crystal structure determination revealed the formation of a one‐dimensional structure belonging to monoclinic crystal system, space groupP21/cwith cell parametersa= 0.8043(1) nm,b= 1.8949(3) nm,c= 1.1048(1) nm, β = 110.109(4)°,V= 1.5810(4) nm3andZ= 4. The crystal was found to be stable up to approximately 300°C by thermal analysis and have an energy gap (Eg) of 2.0 eV exhibited by UV‐Vis‐NIR