Rapid advancements in Information Technology as well as changes in living conditions have led to widespread use of computer games among adolescents. The present study was carried out to indentify parents’ worries about the harm caused to teenagers by computer games. In this research, mixed methods methodology with exploratory design was used. In the first phase, phenomenological, qualitative design was used and 11 adolescents who were selected through snowball sampling were interviewed and in-depth data were collected. In the data analysis, 328 primary codes, 16 subthemes and 3 themes. i.e.,  “physical”, “social and cultural”, and “cognitive and mental” harm, were indentified. In the second phase, quantitative design was used and the statistical population of this stage comprised either mothers or fathers of high school boys in Nahavand. The sample (200 individuals) which was selected via random stratified sampling took a self-devised questionnaire. One-sample T-test, F test, and Tukey’s test were used for data analysis.  Qualitative and quantitative results indicated that computers’ physical, social, and cognitive harm was a matter of considerable concern for parents. Additionally, results of F test and Tukey’s test showed that parents were more worried about computers’ physical harm than their cultural and cognitive harm.