A simple and reliable spectrophotometric method was developed and validated for the determination of methotrexate incorporated into PLGA implants and released from them. The detection of the drug was carried out in 0.1 ml/L hydrochloric acid at 307 nm. It provided specificity for the methotrexate in direct contact with the PLGA. The method was linear in the range of between 4 and 14 μg/mL presenting a good correlation coefficient (r = 0.99). The average accuracies of three concentrations ranged from 98.64 to 100.76 % and precision was close to 2%. The method showed robustness, remaining unaffected by deliberate variations in relevant parameters.The validated method can be successfully applied to determine methotrexate loaded PLGA implants.