Covid-19 vaccine hesitancy among young adults is a current public health issue that needs to be addressed considering the seasonally driven waves of disease and the administration of vaccine boosters. As a prevention measure, the EU Covid certificate had been implemented to increase vaccine uptake, but its application was controversial. Our study investigated students' opinions and attitudes towards Covid-19 vaccination and the EU Covid certificate through a mixed-methods design. An 18-item questionnaire was administered to 200 students during a vaccination campaign in September 2021 at the University of Bordeaux, France. Simultaneously, 30 students attended a semi-structured interview. Collected data were analyzed separately then discussed together through a parallel and convergent approach. Results showed that vaccine hesitancy was high among students, mostly from fear of short-term side effects. However, respondents decided to get vaccinated to obtain the EU Covid certificate, even if they considered it as a violation of their freedom. Straightforward communication about Covid-19 vaccination did not reach students, although this was a strong expectation from governmental and health institutions. Findings suggest that key health personnel should provide evidence-based information about vaccines in efforts of building trust with young people.