Abstract: Objective: To explore the correlation and causality between mindfulness and flow of athletes through two studies, as well as the role of resilience. Methods: In study 1, 269 athletes were recruited and measured with questionnaires. The 2 (experimental conditions) × 2 (time) randomized controlled trial was used in study 2. 66 athletes were recruited and randomly assigned into the mindfulness training group (N=33) and the control group (N=33). The mediating effect of resilience was tested using the method of Bootstrap. Results: In study 1, mindfulness, resilience and flow were positively correlated with each other; Resilience mediated the relationship of mindfulness and flow. In study 2, there was no significant difference in the total scores of the pre-tested indicators between mindfulness training group and control group. Compared with the control group, the subjects in the intervention group showed increased mindfulness level, resilience and flow; Resilience change significantly mediated the relationship of group and flow. Conclusion: Mindfulness can significantly predict athletes' flow; resilience mediates the relationship between mindfulness and flow.