Students assessment is one of the essential components of education to evaluate the effectiveness of a program and decision makings. Antiplagiarism software packages are widely used in many universities and institutions to assess students` performance in their assignments and papers and to give them feedback. This study attempted to investigate students` background and familiarity regarding the concept and kinds of plagiarism, their reasons for plagiarizing, suggestions for avoiding it, and their attitudes toward effectiveness of the anti-plagiarism software Turnitin.Using survey and open-ended questions, followed up by interview, in this study we analyzed collected data from 42 university students in the department of English Language Teaching (ELT) in North Cyprus. This study triangulated data collection tools by using surveys and interviews, also the data were analyzed with SPSS 21.0. The results of survey revealed the students` familiarity with the concept and kinds of plagiarism and their reasons for plagiarizing, open-ended questions concerned with ways of avoiding plagiarism, their attitude toward effectiveness of the anti-plagiarism software, specifically Turnitin and their previous formal studies about plagiarism. In additions, the interview focused on confirmation of survey and open-ended questions as well as the extent of intentionality of plagiarizing and their extra suggestion..