Etoricoxib is a new COX-2 selective inhibitor. Current therapeutic indications are the treatment of rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, chronic low back pain, acute pain, and gout. Like any other COX-2 selective inhibitor, Etoricoxib selectively inhibits isoform 2 of cyclo-oxygenase enzyme (COX-2) to reduce the generation of prostaglandins (PGs) from arachidonic acid. Effective chromatographic separation method for etoricoxib was achieved using HPLC instrument by Luna C18 – (150X4.6mm, 5μm) column with isocratic elution of the mobile phase consisting of buffer pH 3.5 of 0.01M potassium dihydrogen phosphate (1.36g/L): acetonitrile: methanol (40:15:45 v/v/v). The wavelength of detection was set to be 235 nm (UV detector), and a flow rate of 1.0 ml/min was employed, 10 μl was used as injection volume and the column temperature was maintained at 30°C. A rapid, simple, and selective reversed-phase high-performance liquid chromatographic method was developed and validated for the assay of Etoricoxib in its pharmaceutical formulation, under these chromatographic conditions, the peak of Etoricoxib was obtained at a retention time about 5.1 min. and run time of about 7.0 minutes. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, and limit of quantitation. The proposed method can be used for the assay of these drugs in dosage form for routine analysis, this has already been applied to different samples, and this is explained in the applications section.