The lack of originality in the elaboration of academic texts is a prevalent difficulty in university students. Due to the complexity of tasks such as citation and paraphrasing, a significant number of students incur in plagiarism either intentionally or unintentionally. In the present study the process of improvement in the elaboration of argumentative essays in a sample of Peruvian humanities students from a university located in the city of Lima is reported. The plagiarism detection software Turnitin was used as a feedback tool through the use of QuickMarks and text and voice comments. The results of this study have shown that it was possible to significantly reduce the most common types of plagiarism (Search and replacement, Remix and Mosaic); hence, obtaining essays with a greater degree of originality.