Since the 1990s, it has become clear that Belgian girls tend to outperform boys on educational parameters. Similar educational gender gaps are encountered in other western industrialized countries and are often attributed to cultural conventions concerning typical masculinity and femininity, which would inform gendered study cultures. This paper investigates the influence of gendered peer cultures in Flanders on an individual level by employing the concept of pressure for gender conformity. More specifically, the genderdifferentiated impact of gender-conformity pressure is investigated in relation to academic self-efficacy. We examine these inter-and intragender differences in a sample of 6380 seventhgrade students in Flanders (the northern, Dutch-speaking part of Belgium), clustered in 59 schools. The data were collected at the start and the end of the 2012-13 school year. Results from multilevel regression analysis at two waves show that boys' academic self-efficacy is lower when experiencing more pressure for gender conformity. Girls' academic self-efficacy, however, does not decline when experiencing similar levels of pressure. In addition, when taking into account the negative toll that pressure for gender conformity has on girls' wellbeing, their academic self-efficacy is higher when experiencing more pressure. This gender-differentiated impact of pressure for gender conformity is not apparent at the start of the school year, but emerges in the course of seventh grade. The results are discussed in light of gendered expectations for boys and girls in the Belgian context.