COVID-19 has changed not only the way we live but also the form of tourism. With the prolonged COVID-19 pandemic, domestic camping is rapidly emerging as a new leisure trend. This study is differentiated from the existing camping activity study, and will be a timely study to define the meaning of camping activities under COVID-19. The purpose of this study is as follows. In this study, to investigate the effect of camping activities, which have become a trend due to the prolonged COVID-19 pandemic, on the reduction of psychological stress, camping was considered as three factors (travel alternative camping, group camping, and camping), and changes in enjoyment, flow, and stress reduction were investigated. In this study, only 284 validated questionnaires were used for empirical analysis. A preliminary survey was conducted in February 2021, and the main survey was conducted for about a month from February 10. For empirical analysis, SPSS 21.0 and AMOS 23.0 statistical abolition programs were used, and frequency analysis, confirmation factor analysis, reliability, validity analysis, correlation analysis, and structural model analysis were performed. The analysis result of the collected data is as follows. First, it was found that among camping activities under COVID-19, travel alternative camping and group alternative camping affected the enjoyment, while relief-oriented camping did not affect it. Second, it was found that all factors of camping activities under COVID-19 had a significant effect on the flow. Third, the pleasure and the flow had a significant effect on the stress reduction. Based on these results, in this study, strategies and countermeasures were presented, and theoretical and practical implications were discussed.