During quarantine, between March and May 2020, YouTubers disseminated information about Covid-19 and the quarantine. The objectives of this study are (1) to explore whether YouTubers are considered as reliable sources of information regarding quarantine by French social media users, (2) to evaluate the link between the parasocial relationship with a favorite YouTuber and the level of trust in the information provided by this YouTuber and (3) to test the effectiveness of the favorite YouTuber as a source of information about the benefit of quarantine. Data from 596 participants were collected through an online survey, among whom, 251 had a favorite YouTuber. Wilcoxon signed-rank tests and ordered logistic regressions were used to explore two research questions and to test two hypotheses. Results show that (1) information about the benefit of quarantine from the favorite YouTuber is considered just as reliable as information from journalists, friends or family members, (2) the intensity of the parasocial relationship with the favorite YouTuber is positively and significantly associated with the level of trust in that favorite YouTuber, (3) having received trusted information about the benefit of quarantine from one’s favorite YouTubers is positively and significantly associated with the perception of the utility of quarantining. This study identifies YouTubers as important sources for health communication.