The purpose of this paper is to outline the "ecology of social time" as an empirical concept of time to bridge the gap between theory and empirical research in the sociology of time. First, this paper proposes that social time could be considered as an institutionalized referential mechanism that enables social interactions to occur at a specific time point by coordinating the social actions of various agents. Examining the condition of temporal coordination and diagnosing its fairness critically may be the tasks involved in the sociology of time. Second, this paper suggests that the ecology of social time is a useful concept for integrating the theses and tasks applied in the sociology of time. Finally, this paper presents an ecological model of social time as a possible framework for subsequent empirical research in the sociology of time.