Determining whether gender-related differences exist in the linguistic characteristics of writing in formal contexts is one of the concerns of recent research on gender in second language writing. This study aimed to explore gender differences in undergraduate argumentative writing in English as a foreign language (EFL) in terms of lexical and discoursal features. Around 100 Persian-speaking male and female EFL learners with insignificant differences in English proficiency at the time of the study and with similar background literacy experiences performed an opinion-based writing task under exam conditions. Combined corpus analysis and discourse analysis techniques were used to describe and compare their texts in terms of writing quality, lexical properties, and rhetorical organization. Results showed that a) male learners received significantly higher mean scores in the content and organization of their argumentative writing (t= 2.03 and 2.08 respectively, p≤ 0.04); b) female EFL learners wrote less assertively and expressed positions more obscurely as shown in the analysis of their topic sentences; and c) While male learners used both inductive and deductive overall organizations for their texts, most female learners (74.4%) wrote more deductively. Results of concordance and keyword analyses through Wordsmith Tools also illustrated that learners’ social and ideological contexts of gender contributes to their approach to academic writing in English. تفاصيل المقالة