This experiment was designed to examine the effects of gender role and task content on performance in learning a dyads and to test the potential mediator effect of an intragroup process related to transactive memory. A total of 44 same-gender dyads participated in the study, and were asked to collaborate on a stereotypically, masculine or feminine task in a laboratory selling. Collective performance and transactive memory were measured As predicted, the results showed an interaction between group gender and task content on group performance, with male dyads showing poorer performance on a masculine task than female dyads. However, contrary to expectations, this moderation effect was not mediated by transactive memory, which appeared as a simple mediator of the relationship between group gender and performance. The results are discussed in the framework of the social role theory, and implications for future research in small learning groups are proposed.