Sexual science has often been mobilized to advance progressive sexual rights agendas against conservative, religiously-driven political agendas. This chapter explores a different dynamic, where religious-conservative activists used sexual science to advance their ‘anti-homosexual’ campaign. We focus on the attacks on Kinsey in the US. While the historiography on religious conservatism has highlighted the centrality of religious/moralistic discourses, our analysis of textual sources (from archives of evangelical-political organizations and recently declassified FBI documents) shows that evangelical activists often foregrounded scientific arguments. Women activists played a particularly important role in this discursive battleground, as our political history of the attacks on Kinsey demonstrates.