This study proposes a model on the relationship between cultural ecosystem service (CES) and visitors’ subjective well-being (SWB). The model consists of the four constructs of CES, SWB, place attachment, and event attachment, which are developed from literature of multiple disciplines. The model is tested with primary data collected in a China’s national park and its 10th Flower Expo. The results indicate that perceived value of CES has strong direct effect on visitors’ SWB, as well as a serial mediating effect through place attachment and event attachment. Perceived value of CES is an important antecedent of place attachment, event attachment, and visitors’ SWB. When controlling the effect of CES, event attachment exhibits a significant effect on visitors’ SWB, but the effect of place attachment is insignificant. In addition to the proposed model, the study’s findings provide fresh empirical evidence to further understand each of the four constructs and their interrelationship.