Although an increasing amount of the leadership literature argues that leader humility is beneficial to team learning, few studies have examined this effect directly and, as such, little is known about why leader humility has such important effects or when these effects can be amplified or attenuated. Utilizing a survey of 305 employees on 89 teams, we found a positive relationship existing between leader humility and team learning. The results also indicated that a shared mental model was an important mechanism revealing why leader humility could stimulate team members to learn. In addition, we found that the learning effect stimulated by leader humility was much stronger on teams having a high collective promotion focus instead of a high collective prevention focus. Theoretical implications and managerial practices were also discussed.