Transactive memory systems (TMSs) are known to play a role in determining team performance by assigning each team member with tasks most relevant to his or her skills and coordinating members’ expertise. However, because not much is known about the negative and organizational factors of TMSs, this study examined the relationship between TMSs and organizational climates under pressure as the negative factor. Furthermore, this study investigates how certain factors mitigate negative effects on TMSs. Gender diversity is examined as an important aspect of the relationship because TMSs rely upon the cooperative division of cognitive labor in teams, and team diversity facilitates information sharing in groups. Thus, one purpose of this research is to examine how organizational climates under pressure and gender diversity influence TMSs. Another purpose is to examine how TMSs impact team performance. To achieve these purposes, data were collected from 25 teams of a Japan pharmaceutical company, including 183 followers and managers. The study yielded three major results: (1) High-pressure organizational climates were negatively related to TMSs. (2) Gender diversity moderated the relationships between high-pressure organizational climates and TMSs. The negative relationship between organizational climates under pressure and TMSs weakens as gender diversity increases, indicating that gender diversity reduces the negative effect of organizational climate under pressure on TMSs. (3) TMSs have a positive impact on team performance. The findings of this study suggest that (1) examining organizational climates under pressure as a negative factor is important in understanding TMSs’ development and (2) gender diversity is a factor that mitigates the negative effects.