Although the importance of leadership for innovation processes has been acknowledged, the understanding of the relationships between leadership styles and levels of innovation in work teams is still limited. This study among team managers and team members of 133 Spanish bank branches (i.e., work teams) investigated whether the influence of charismatic leadership on work team innovative behavior comes about via team potency, and whether the relationship between charismatic leadership and team potency is moderated by the level of task interdependence within the team. Data were collected at three different time points. Results of structural equation modeling showed that only at high levels of task interdependence, team managers’ charismatic leadership at time 1 was significantly positively related to an increase in team potency at time 2, which in turn was positively related to manager ratings of their work teams’ innovative behavior at time 3. This means that only at high levels of task interdependence, charismatic leadership had a significant indirect effect on team innovative behavior via team potency. Thus, our study sheds light on the boundary conditions of this effect.