By reviewing the literature, there is no indication concerning the use of Leishman’s dye in evaluating drug compounds by dye-color bleaching; hence, it is the first attempt to use Leishman’s dye as a novel reagent in the estimation of chloramphenicol (CAP) by an indirect spectrophotometric method in bulk and in its pharmaceutical preparations. The method includes the use of a great amount of N-bromosuccinamide (NBS) in the acidic medium as an oxidizing agent of the drug under investigation (CAP), and then using the residual of NBS for Leishman’s dye color bleaching. The absorbance has been measured at 622 nm (the maximum absorption of Leishman’s dye). A linear relationship was obtained for the Beer’s law with the concentration ranges from 10 to 250 μg/10 mL with acceptable values of molar absorptivity 0.58 × 104 L.mol-1.cm-1 and 0.055 μg.cm-2 of Sandell’s sensitivity index, which mean a high sensitivity. An approved estimation of CAP in its various pharmaceutical formulations was found.