This study analyzes the interactions based on student gender that are promoted by future primary school teachers, with three distinct profiles in the subjects of natural sciences and math. The three teacher profiles combine socioemotional variables related to the teaching of these two subjects and variables related to gender bias. 17 class videos of both mathematics and natural sciences in the context of pre-service teacher preparation were analyzed regarding the interactions that took place. A prevalence of interactions directed towards boys was found. Regarding the type of profile, it was found that pre-service teachers with masculine traits promoted more interactions with gender equity. The implications for primary teacher preparation and for the creation of school environments in which girls are encouraged to engage in mathematics and natural sciences are discussed.