Organizational effectiveness is contingent upon employees' contributions; however, the role of employee voice behavior as a critical component of employees' contribution to the organization has not been sufficiently acknowledged. Based on proactive behavior theory, we present a model to investigate employee voice behavior as an underlying mechanism in the relationship between supervisor delegation and perceived workplace inclusion. Using the SEM (structural equation modeling) method, we test our model's hypotheses with data from 271 employee-supervisor questionnaires administered in state-owned enterprises in the telecommunications industry. The results show that supervisor delegation is positively related to employees' promotive and prohibitive voice behavior. Promotive voice significantly influences perceived workplace inclusion, but prohibitive voice behavior was not found to have any impact on perceived workplace inclusion. Moreover, both dimensions of voice behavior, i.e., promotive and prohibitive voice behavior, significantly mediate the relationship between supervisor delegation and perceived workplace inclusion.