In recent years, China’s growing global economic influence has attracted more foreign workers, requiring leaders to have effective communication skills to manage diverse personnel to drive innovations. Although previous research studies revealed the effects of a leader’s motivating language (ML) on employee’s innovativeness, the mechanism and the boundary conditions for stimulating the relationship between ML and innovative work behavior (IWB) are scarce. Therefore, this study aims to examine employee’s creative self-efficacy (CSE) as a mechanism and coworker support (CS) as a boundary condition in the relationship between ML’s dimensions and IWB. To test the moderated mediation model, this study collected the data from 283 workers and their respective supervisors at a Beijing-based multinational network company. The research applied a quantitative approach. SPSS and AMOS were used to analyze the data. ML’s dimensions are positively linked to IWB. CSE was found as a mediator in these relationships. CS did not play its moderation roles on ML – CSE, ML – IWB direct or ML – IWB indirect (via CSE) links. ML’s direction-giving speech is found to be more effective in predicting CSE and IWB. This is the first paper to examine the impacts of the three dimensions of ML on IWB.