Based on paper substrate room temperature phosphorescence, the chiral discrimination of quinine and quinidine was achieved using Whatman No. 40 filter paper as the substrate and Pb(Ac)₂ as the heavy atom perturber. The phosphorescence lifetime differences between quinine and quinidine increased from 4.45% to 27.90% upon addition of (+)-tartaric acid as the chiral modifier. This provided a rapid and simple method for the determination of the enantiomeric composition of quinine and quinidine.