Abstract: The present invention relates to a method for monitoring error in prescription data employing barcode system comprising the steps of recording a dosage type and dose of a medicament in a prescription order by way of encoding those in a form of barcode, inputting information recorded in the barcode-prescription order, comparing the information with a database information about the prescribed medicament, and displaying the appropriateness of the dosage type and dose of the medicament. In accordance with the method for monitoring error in prescription data employing barcode system of the invention, the error in prescription data including dosage types and doses of prescribed medicaments can be reconsidered, which makes possible its practical application for the treatment of diseases in a more safe manner.