A new class of platinum(ii) acetylide complexes with urea group, [Pt((t)Bu3tpy)(C[triple bond, length as m-dash]CC6H4-4-NHC(O)NHC6H4-4-R)](OTf) ((t)Bu3tpy = 4,4',4''-tri-tert-butyl-2,2':6',2''-terpyridine; R = H (), Cl (), CF3 (), and NO2 ()), has been synthesized and characterized. The crystal structures of , ·DMF·THF, ·CH3CN, and ·CH3CN have been determined by X-ray diffraction. Upon excitation at λ > 380 nm, the solid samples of complexes show orange light at 298 K. The anion binding properties of complexes have been studied by UV-vis titration experiments in CH3CN and DMSO. In general, the log K values of with the same anion in CH3CN depend on the substituent R on the acetylide ligand of and follow this order: R = NO2 () > CF3 () > Cl () > H (). For the same complex with different anions, the log K values are in the following order: F(-) > OAc(-) > Cl(-) > Br(-) ≈ HSO4(-) ≈ NO3(-) > I(-), which is in accordance with the decrease in the basicity of anions. Complex with NO2 group shows a dramatic colour change towards F(-) in DMSO, allowing the naked eye detection of F(-).