Two simple, precise, accurate and economical UV spectrophotometric methods have been developed and validated for the routine estimation of moxifloxacin HCL in bulk drug and pharmaceutical formulation. The drug shows maximum absorption at 293nm and obeyed Beer-Lambert’s law in the concentration range of 1-20μg/ml. The same spectrum was derivatised into first order derivative. The amplitude of trough at 282nm and crest at 302nm for D1 were measured. In D1 method the drug showed linearity in the concentration range of 1-20μg/ml. The linear regression equations were calculated to be y=0.0966x+0.031 (R2=0.9949) for D0 at 293nm, y= -0.0044x+0.0004 (R2=0.9937) for D1 at 282nm, and y=0.0056x-0.0005 (R2=0.9962) for D1 at 302nm. The results of estimation of marketed tablet formulations were found to be 98.241±0.669-100.678±0.537 for tablets and 99.172±0.514- 100.362±0.471 for eye drop with their SD less than 2. Recovery studies were carried out by addition of known amount of standard drug (80,100 and 120% of labeled claim of a tablet) to the preanalysed tablet solution. The % recovery was found to be 98.745-100.984 for tablets, and 98.124-100.174 which indicates accuracy and reliability of the validated method as well as noninterference from excipients to the developed method. The intraday and inter day assay was within 2%. The methods were then validated statistically as per the ICH guidelines which yielded good results concerning range, precision, accuracy, specificity and repeatability.