Abstract: [Purpose/Significance] With the development of the Internet and the popularization of smart devices, the scale of social media users around the world is increasing, and social media has become the center of people's communication, but it also produces a series of negative problems. Digital stress refers to the painful subjective experience of users caused by different stressors in the process of heavy use of social media. At present, most studies on social media focus on users' social media behaviors. In recent years, digital stress has gradually attracted the attention of researchers. However, most studies discuss the impact of single variables on results from the perspective of linear regression, and few studies focus on the complex mechanism behind digital stress. This study aims to explore the influencing factors and mechanism of social media users' digital stress in order to further understand the path of digital stress and provide reference for relieving users' digital stress. [Method/Process] This paper adopted a mixed research method combining grounded theory and qualitative comparative analysis. First, 21 users were selected as interview objects, interview data were coded, and theoretical models were constructed. Second, a questionnaire was designed according to the theoretical model and 262 questionnaires were collected. The fuzzy set qualitative comparative analysis (fsQCA) method was used to analyze the questionnaire data and explore the formation path of social media users' digital stress. [Results/Conclusions] There were 9 influencing factors of social media users' digital stress: overuse, technology intrusion, information overload, communication load, fear of missing out, approval anxiety, social expectation, digital coping skills and self-control. They were classified into four dimensions: technology, social, environment and personal characteristics. There are six paths that trigger digital stress, among which overuse and fear of missing out are the key factors leading to high-level digital stress, technology intrusion and information overload are the important conditions for digital stress, and digital coping skills and self-control have no significant effects. At the same time, this paper has some limitations. First, the end point and result variable of this paper is the digital pressure of social media users, focusing on the factors that affect the generation of digital pressure and how the combination of factors and variables ultimately leads to the generation of results. Less attention is paid to user behavior. Although some attention is paid in the interview, antecedent variables are emphasized in the analysis. Future studies can take users' social media usage behavior into consideration to explore the whole process formation mechanism of influencing factors-digital pressure-user behavior. In addition, most of the research samples are young users of social media, and users of other age groups are less involved. In the future, the research samples should be further expanded to improve the universality of the research conclusions.

Key words: digital pressure, social media, influencing factors, qualitative comparative analysis, information behavior