This paper applies an economic game theory model to explain the decisive mechanism of organizational citizenship behavior (OCB). The Sub-game Perfect Nash Equilibrium (SPNE) indicates that an employee’s unique motivation of OCB is to maximize his or her own performance outcome. The findings also suggest that workload, importance of work to performance outcomes and cost of OCB jointly determine the amount of OCB that each individual employee exhibits. An empirical test utilizing frontline hotel employees was performed (N = 175). Using a partial related test and logistical model, the results supported three propositions, suggesting that the amount of OCB exhibited by each employee is jointly influenced by the workload, cost of OCBs and OCBs performed by coworkers