Colorimetric chemosensors are now considered as one of the most effective analytical method used in the environment monitoring. Colorimetric chemosensor for pH sensing can easily detect the primary danger or change of the surrounding environment pollution and source of infection and can prevent danger in the various fields. Quinaldine and Indole based colorants having the function of colorimetric chemosensors were synthesized. Each colorants are confirmed to compare the result of mass spectra with calculated mass of Quinaline and Indole respectively. UV-Vis spectroscopy revealed that the colors of each colorants solutions were changed in basic conditions while no changes were observed in acidic conditions.