Sirolimus is a macrolide compound used to prevent organ transplant rejection. A UV spectrophotometric method has been developed for the estimation of sirolimus in the tablet. Ethanol is used as a solvent. Sirolimus has shown absorbance maxima at 278 nm. The method was validated according to ICH Q2 (R1) guidelines. The method is linear in the range of 5-30 ?g/ml and exhibited a good correlation coefficient (R2=0.9992) with a recovery of 98-100% and precision. The developed analytical method is simple, accurate, precise, and can be applied for routine analysis of formulation containing Sirolimus in a short time.