The influences of the substituent base position on the excited state intramolecular proton transfer fluorescence prop-erties were explored in 2-(2’-hydroxyphenyl)imidazo[1,2-a]-pyridine (HPIP) and HPIP’s derivatives (5’Br-HPIP and 6’Br-HPIP). And the density functional theory (DFT) and time-dependent DFT (TD-DFT) methods were used to calculate the molecule structures. The calculated results showed that the influence of 5’Br-HPIP on the fluorescence intensity is stronger than that of 6’Br-HPIP. The fluorescence emission peak of 5’Br-HPIP occurred a blue shift compared with HPIP, and 6’Br-HPIP exhibited an opposite red shift. The change of the fluorescence emission peak was attributed to the decrease of the energy gap from 6’Br-HPIP to 5’Br-HPIP. Our work on the substituent position influence could be helpful to design and develop new materials.