People with mental illnesses (MIs) face several challenges in addition to their disease. People’s negative views of those with MIs impact patients’ decisions to seek professional help. The aims of this study were to assess pharmacy students’ attitudes toward people with MIs and seeking help for mental health, as well as their knowledge about the causes of MIs. A cross-sectional survey was conducted on pharmacy students at Unaizah College of Pharmacy, Qassim University, Saudi Arabia. Out of the 460 distributed questionnaires, 330 complete questionnaires were received, giving a response rate of 71.7%. Overall, the mean total score for attitude towards people with MIs was 60.16 ± 10.48 (maximum attainable score: 105). In this study, 51.12% believed that people with MIs are more likely to harm others than a person without MIs and 66.9% mentioned that they did not trust the work of a mentally ill person as part of their work team. However, only 35.45% believed that it is difficult for mentally ill individuals to follow social rules. In terms of attitudes toward help-seeking, the mean total score of was 12.83 ± 3.16 out of the maximum score of 25. In addition, the mean total score for knowledge about causes of mental illness was 2.92 ± 1.76 out of the maximum score of 8. The participants reported that MIs could be due to genetic inheritance (56%), substance abuse (54.5%), or brain disease (66.1%). The findings showed that there are some negative attitudes toward people with MIs and negative attitudes towards seeking help for mental health. In addition, some misconceptions about the causes of MIs are prevalent. Consequently, the incorporation of more topics concerning mental health in pharmacy curricula could help improve the awareness of and knowledge about mental health.