The mental health of young people, a significant public health concern worldwide, has deteriorated during the COVID-19 pandemic. Despite the subsiding of the epidemic, the issue remains unresolved in the post-pandemic era, specifically in China. In response, numerous art museums have stepped up to provide long-term therapeutic experiences and comprehensive mental health support. While these institutions offer a variety of services and programs aimed at enhancing the psychological wellbeing of their visitors, a standardized method for assessing their impact is lacking. This study, therefore, employed the Generic Wellbeing Questionnaire (GWQ) as a tool to evaluate the decrease in psychological anxiety among young museum-goers postvisit. A survey was conducted among 306 young visitors aged 15-24 at the Aurora Museum in Shanghai, using the GWQ to measure and compare positive and negative affects before and after their visit. The results revealed an increase in post-visit positive affects and a decrease in negative affects compared to pre-visit levels. All items measured contributed to changes in psychological anxiety, demonstrating that museum visits can alleviate such anxiety among young audiences. Interestingly, while "alert" is considered a positive affect in Western contexts, it is found to be adverse in Chinese contexts, suggesting that it may not be an appropriate item for positive affect. The GWQ thus emerges as a potentially effective tool for evaluating interventions aimed at reducing psychological anxiety among young audiences in Chinese museums.