Simple, fast and reliable derivative spectrophotometric methods were developed for determination of Aprepitant in bulk and pharmaceutical dosage forms. The solutions of standard and the sample were prepared in methanol. The quantitative determination of the drug was carried out using the zero order derivative values measured at 210 nm and the first order derivative values measured at 269 nm (n=6).Calibration graphs constructed at their wavelengths of determination were linear in the concentration range of Aprepitant using 6-14 μg.mL-1 (r² = 0.998and r² = 0.998) for zero order and first order derivative spectrophotometric method. All the proposed methods have been extensively validated as per ICH guidelines. There was no significant difference between the performance of the proposed methods regarding the mean values and standard deviations. Developed spectrophotometric methods in this study are simple, accurate, precise and sensitive to assay of Aprepitant in tablets.