Did women play a role in the adoption of proportional representation system? In this paper, we explore how women’s suffrage at the turn of the 20th century shaped politicians’ propensity to vote for the adoption of proportional electoral system (PR) in Norway. Extant literature uncovers two broad explanations for adoption of PR. One emphasizes strategic/instrumental incentives of parties and employers (e.g. Leemann and Mares 2014; Cusack et al 2010; Boix 1999; Cox et al 2018). The other emphasizes normative-based demands from voters and politicians (Blais et al 2004; Bol et al 2015). However, neither account considers the role of women. Whilst most Western countries that adopted PR at the turn of the twentieth century did so before women gained equal voting rights, this was not always the case. A notable exception is Norway (see Skorge 2023, Teele 2023), where women’s suffrage (1909, 1915 election years) was adopted before the switch to PR at the national level (and partly also local level) (1921 election year). In this paper, we fill this gap by studying the role of women in adopting PR in Norway. Utilizing sex-separated data on turnout and roll calls of legislative support for PR, we find that politicians were more likely to support PR adoption in districts with high female turnout. By showing that men’s turnout is not correlated with politicians’ propensity to support PR, we cast doubts on the possibility that these results reflect men’s preference for PR or demands for greater democratization of a highly active electorate.