This study aimed to examine the effects of the participating motivation and flow experience on knowledge sharing of university faculty members in faculty learning communities (FLC). A total of 192 faculty members participated in FLC and responded to the survey questionnaire. Pearson’s correlations and stepwise regression analyses were used to determine the relationship in participating motivation, flow experience, and knowledge sharing. The results revealed that the most highly recognized factors were affiliation motive, achievement motive, and concentration flow. Both the dimensions of participating motivation and flow experience were highly correlated with each other and strongly predicted knowledge sharing. The result of stepwise regression analyses revealed that the factors of achievement motive, power motive, concentration flow, and challenge flow were found significantly to predict knowledge sharing in FLC. Among these factors, the concentration flow was the most powerful predictor on knowledge sharing which was also the core element of the flow experience dimension. The flow experience of faculty members in FLC was different from that of the other online learning communities. The position of an individual faculty member in FLC and the role of the leading faculty member were discussed for future research. Both theoretical and empirical aspects were crucial for promoting practical work in order to realize the positive psychological mechanism of knowledge sharing in faculty members.