A triphenylamine substituted Ir(Ⅲ) complex Ir-TPA was designed and synthesized by the modification of the cyclometalating ligand 2-phenylpyridine. Then Ir-TPA was employed as a luminescent probe for the detection of nitroaromatic compounds (NACs) include 4-nitrotoluene, 1,3-dinitrobenzene, 3-nitrobenzoic acid, and 3-nitrobenzyl alcohol. The Stern-Volmer equation was employed for the fitting of test data. The highest detection efficiency of Ir-TPA was demonstrated to 3-nitrobenzoic acid with KSV of 6.18?0.10 mM-1 and the detection limit down to 0.0112 mM. The detection mechanism of Ir-TPA to four NACs was assigned to the charge transfer which has been indicated by spectral analysis and density functional theory calculation. This study provides theoretical and technical support for the rapid and efficient detection of NACs.