A simple, Accurate, precise method was developed for the estimation of the Irinotecan in API and Marketed Pharmaceutical Dosage forms. Chromatogram was run through Symmetry ODS (C18) RP Column, 250 mm x 4.6 mm, 5µm. Mobile phase containing Acetonitrile, Methanol and 0.1% Ortho Phosphoric Acid taken in the ratio 60:30:10% v/v/v was pumped through column at a flow rate of 1.0 ml/min. Buffer used in this method was 0.1% OPA. Temperature was maintained at Ambient. Optimized wavelength selected was 235 nm. Retention time of Irinotecan was found to be 2.570min. %RSD of the Method Precision for Irinotecan were and found to be 0.768. %Recovery was obtained as 100.59% for Irinotecan. LOD, LOQ values obtained from regression equations of Irinotecan were 0.08 and 0.24 respectively. Regression equation of Irinotecan is y = 19423x + 5444.4 of Irinotecan. Retention time was decreased and run time was decreased, so the method developed was simple and economical that can be adopted in regular Quality control test in Industries.