A treetop trail is an elevated linear green open space that plays a key role in forming a scientifically rational urban space and meeting the growing leisure needs of the people. Taking the Mountains-to-Sea Trail in Xiamen, China as a case, and through 426 questionnaires, this study explores the dimensions of the perceived restorative environment components of greenway recreationists and impacts on behavioral intentions. The demographic factors lead us to the following three conclusions. First, from an age perspective, restorative environmental perceptions are strongest among those aged 60 and above and weakest among those aged 18–30. Second, in terms of place of permanent residence, local visitors have stronger restorative environmental perceptions than other city users. Third, in relation to the number of accompanying travelers, individuals who embark on solo journeys experience the most robust perception, while that diminishes as the count reaches three or more companions. A structural equation model (SEM) is used to present the quantitative relationship among avoidance motivation, treetop trail environmental quality, restorative environmental perception, place attachment, and loyalty. The results showed that users’ escape motivation has a direct and indirect positive correlation with restorative environmental perceptions, and environmental perceptions have a significant positive correlation with restorative environmental perceptions. Furthermore, their place attachment to the restorative nature of the treetop trails positively affected their loyalty. This study provides essential factors to consider when constructing treetop trails in high-density cities.