Three new heteroleptic Ir(III) complexes o-LIrpic, m-LIrpic, and p-LIrpic (L = CF3DPQ) consisting of 2,4-diphenylquinoline (DPQ) with a –CF3 group at ortho (o)/meta (m)/para (p) positions of the metalated phenyl ring, respectively, as the main ligands were synthesized and used as emitters in phosphorescent organic light-emitting diodes (PhOLEDs). We realized that –CF3 position extremely affects the crucial photophysical and electronic properties such as emission color, photoluminescence quantum yield (PLQY) and energy levels of these Ir(III) complexes resulting in –CF3 position-dependent performance of their PhOLEDs. To verify the effect of –CF3 group position on device performance, three other Ir(III) complexes o-LIrtmd, m-LIrtmd, and p-LIrtmd were synthesized using the same main ligands but a different ancillary ligand. In the two series of Ir(III) complexes, the devices with m-CF3 based complexes are outstanding in performance compared to o- or p-CF3 based ones due to the enhanced PLQY and well suppressed non-radiative deactivations by m-substitution. Finally, the single emission layer solution-processed orange and two-component white PhOLEDs fabricated using m-LIrpic as orange emitter achieved the maximum external quantum efficiency of 17.1% (43.9 cd A−1) and 21.1% (48.8 cd A−1), respectively, with highly stable color coordinates and low efficiency roll-off. This is the highest efficiency reported to date for solution-processed orange PhOLEDs using a small molecular host with easily accessible emitter.