As a part of a larger project, this study reports a large-scale investigation of the impacts of the Iranian National University Entrance Examination (INUEE) on Iranian high school students and their parents. For this purpose, in a mixed methods research design, 1350 high school students selected based on convenience sampling from three western provinces of Iran were given a researcher-made Likert scale questionnaire; moreover, 27 parents sat for a semi-structured interview. The quantitative data obtained from the questionnaire were subject to inferential statistical analyses, and the qualitative interview data were first transcribed, and then the transcriptions were subjected to content analysis to extract common patterns and recurring themes. The integrated results obtained from the quantitative and qualitative data analyses indicated that from most of the participants' points of view, INUEE had detrimental impacts on students' and their parents' educational, personal, and social life. From students' perspective, INUEE had the most harmful impact on their physical and psychological well-being, and from parents' vantage point, the most negative impacts of INUEE were on the economy of the family and their social activities and entertainments. The findings of the study provide further evidence of the consequential invalidity of such large-scale high-stakes tests and the negative consequences following them. Furthermore, the attested negative impacts of high-stakes large-scale testing on the test takers, their family members, and the educational systems jeopardize educational justice in general and the usefulness and fairness of such tests in particular.