Background: The psychology of vaccination behaviour explains how thoughts and feelings influence people’s willingness to receive vaccines. Understanding vaccination behaviour is crucial to successfully managing vaccination campaigns.Aim: Investigating factors associated with immunisation stress among students at Mohammed First University.Setting: This study was conducted on students at Mohammed First University institutions.Methods: This study is a descriptive and analytical cross-sectional study. It was conducted on 305 students at Mohammed First University institutions using a 90-item questionnaire.Results: Three hundred and five participants have been included in this survey. Overall, 65.5% of the students in our sample had a positive perception towards COVID-19 vaccines. Nevertheless, 34.5% had a negative opinion regarding immunisation. According to the analysis of perceived stress scale, 40% (n = 122) of students expressed moderate to high stress regarding vaccination. Students with a negative perception of vaccine showed a higher level of stress than those with a positive one. Stressed students tended to be older than others, coming from other institutions, other than the medical faculty, and were renting alone. Vaccine accessibility was the less significant reason associated with stress regarding vaccination. Moreover, participants with high levels of confidence in social media, exhibited higher stress. Nevertheless, those who believed in scientific journals were significantly less stressed.Conclusion: These results reflect a positive perception and acceptance of vaccines, with a considerable level of stress regarding vaccination.Contribution: This study suggests emphasising the mental health of Moroccan young adults, to better sensitise and inform them about immunisation.