Applying sexual selection theory to language, it can be assumed that high verbal proficiency increases attractiveness, but male more than female attractiveness, because women have higher costs regarding reproduction and are thus more selective in mate choice. These predictions were tested experimentally. In the first study, videos were used as the stimuli for opposite-sex participants where an actor/actress performed verbal self-presentations. The content was alike but was delivered with three levels of verbal proficiency with respect to lexical, grammatical, and fluency features. The main effect of verbal proficiency on attractiveness was supported, but the interaction effect was not supported between verbal proficiency and sex according to which male more than female attractiveness is affected by verbal proficiency. In the second study, only audio tracks from the videos were used. Both effects were significant, supporting the assertion that language plays a significant role in mate choice, especially for male attractiveness.