Acyclovir is an Antiviral medication. It is primarily used for the treatment of herpes, Simplex virus infections, Chickenpox, and shingles. Simple, precise, accurate and economical UV spectrophotometric methods have been developed and validated for the routine estimation of Acyclovir in bulk and pharmaceutical Dosage form. The Stability indicating method was developed and validated in the present work. The parameters Linearity, Precision, Accuracy, Robustness, LOD, LOQ, system suitability was studied as per the ICH guidelines. Acyclovir shows maximum wavelength at 252 nm. The method was found to be specific without any interference and precise with %RSD less than 2. The LOD & LOQ were found to be 0.030 µg/ml and 0.062 µg/ml. The robustness results were satisfactory by changing the λ max by ± 2nm. The accuracy of the method was determined by recovery studies obtained as 99.72%. The drugs showed degradation for acid, base and peroxide and no degradation for photolight while performing forced degradation studies. Thus the proposed method was found to be accurate, simple & can be used for routine analysis. Keywords: UV Spectrophotometry, Acyclovir, Pharmaceutical Dosage form