Globally, the novel COVID-19 has been recognized as one of the most important pandemics and devastating diseases in human history, with many deaths and morbidities. In the absence of effective treatment and limited supply of COVID-19 vaccine, people must adhere to recommended preventive measures. This study aimed to determine the level of COVID-19 knowledge, perceived susceptibility, perceived severity, and health information-seeking and preventive behaviors as well as associated factors with preventive behaviors in a sample of Iranian students at Persian Gulf University. Data was collected using an online structured and validated questionnaire. Descriptive statistics, the Mann-Whitney U, Chi-square, and Spearman correlation tests were applied to analyze data. The significance level was set at P < 0.05. In total, 98% (319/325) of the participants completed the survey. A majority of participants were aware of the three main COVID-19 symptoms: fever, dry cough, and shortness of breath, while half of them were unaware of gastrointestinal problems caused by COVID-19. More than half of the subjects had a low perceived susceptibility and severity toward COVID-19. Most of the participants engaged in preventive behaviors and got COVID-19 information from social media and the Internet. Preventive behavior was associated with perceived susceptibility (P = 0.015), perceived severity (P = 0.014), and health information seeking (P < 0.001) of individuals toward COVID-19. The results of our research can help health authorities develop health promotion programs for student populations by providing baseline data.