In linguistic academic research, gender differences are often reflected in discourse patterns, vocabulary selection, and intonation. This paper focuses on the discourse expression of gender differences in the English language, using the film Legally Blonde as a specific case study. The dialogues of different gender roles in Legally Blonde exhibit typical characteristics. Through the analysis of this film, it is found that male discourse tends to be more direct, concise, and authoritative, while female discourse contains more emotional nuances and euphemistic vocabulary. From a pragmatic perspective, this difference effectively reflects societal role expectations for different genders. Through an in-depth study of the character dialogues in the film, this research helps reveal the forms of gender differences in English discourse expression, providing new perspectives for better understanding the relationship between gender and language in cross-cultural communication and language learning, as well as offering a reference for eliminating language biases caused by gender.