With increasing environmental dynamics and task complexity, the issue of the creativity of knowledge-based teams has attracted extensive academic attention. One important way to address the issue is to investigate the role of the team leader in facilitating team creativity. Previous studies on leadership have focused on either the leader’s personal characteristics, or her/hisbehaviors, or therelationships with their followers. The first of the approaches known as the trait theory of leadership has received renewed attention in recent years. The trait theory is particularly relevant to team creativity, since the process of team creativity is essentially cognitive. It is our assumption that a team leader'slogical reasoning and creative thinking will have an important effect on team creativity. In a knowledge-based team, the leader faces a special managerial situation. Within the team, vertical hierarchies and commands are replaced by horizontal interaction and communication. The leader retains the identity as a knowledge worker, but s/he generally lacks clear managerial responsibilities. This gives rise to certain role ambiguities. The team leader is expected to undertake the responsibilities of allocating tasks, handling conflicts, and dealing with contingencies. To conduct these activities, the leader needs good logical reasoning. Meanwhile, the leader also plays an important role in generating creative ideas and stimulating team members intellectually. For this purpose, the leader needs to be a creative thinker her/himself. The question is, in most real-life situations, where the leader is not equipped with both sets of cognitive skills (i.e. logical reasoning and creative thinking), which one facilitates team creativity more?This study explores the prioritization of the two thinking abilities for a leader in a knowledge-based team. We argue that a high level of logical reasoning is more important than a high level of creative thinking in facilitating team creativity. On one hand, a considerable number of previous researches indicate that in the process of creative teamwork, aneffective leadership role is usually a supportive rather than a dominant one. According to the dominance complementarity theory, a leader with a high level of logical reasoning is more effective than one with a high level of creative thinking ingenerating creative teamwork. This is because the logical leader is committed to establishing external ties, provides members with both resource and structural support, and promotes members’ psychological empowerment, intrinsic motivation and self-efficacy, whichultimately increases the overall creative output of the whole team. On the other hand, drawing on the idea that human attention capacity is limited, we argue that it is a waste of the team's creative resources to appoint an individual with a high level of creative thinking ability as the leader.As this appointed leader would then invest considerable time and attention in managerial responsibilities and fail to use her/his limited cognitive resources to produce creative work,the team’s overall creativity wouldsuffer consequently. Thus, we hypothesize that a leader with a high level of logical reasoning will bringa higher level of team creativity than a leader with a high level of creative thinking. This hypothesis issupported by both a laboratory study and a case study. This study makes a two-fold contribution. First, by highlighting leaders’ cognitive abilities and variances, it adds importantly to the body of literature that explores the effect of leaders’ personal traits on team creativity. Second, by focusing on team leaders rather than high-level executives, the study also sheds further light on the management of knowledge-based teams. At the team level, a high level of logical reasoning ability rather than creative thinking ability will make a good leader.