The performance of platform flexible employees is a core element that contributes to the rapid growth of the sharing economy platform. It is crucial to explore strategies to improve employees' performance with the growing competition among these platforms. Only a handful of research evidence has been found evaluating platform flexible employees' psychological capital and work engagement to improve their performance. In order to remedy the gap, we draw on self-determination theory to develop a moderated mediation model, which examines how psychological capital affects platform flexible employees' job performance. We employed hierarchical regression analysis to test the theoretical model and carried out two rounds of surveys, resulting in 474 valid paired questionnaires. The questionnaire assessed the psychological capital, work engagement, job performance, and job autonomy of flexible platform employees. The results indicate that work engagement plays a mediating role between psychological capital affects platform flexible employees' job performance. Moreover, job autonomy moderates the mediating effect. The findings not only contribute to the literature on employees' psychological capital and job performance, but also broaden the research scope of self-determination theory, and provide new ideas for improving the job performance of platform flexible employees.
