<p>Incidental vocabulary acquisition can occur through various input materials, including audio, text, video, and text plus audio. Dual modality refers to the simultaneous presentation of information via two modes, typically spoken and written. Although dual modality input is posited to enhance incidental vocabulary learning, research comparing its effects with those of single modality input has yielded inconsistent findings. Moreover, few studies have investigated the effectiveness of pop songs under a dual modality condition (audio combined with lyrics) for facilitating incidental vocabulary learning, and even fewer have compared this with single modality (audio-only) input. The current study addresses these gaps by comparing the impact of listening to a pop song with lyrics versus listening without lyrics on incidental vocabulary acquisition. To achieve this, 114 participants were divided into three groups: no intervention, listening with lyrics, and listening without lyrics. Learning gains were measured through spoken form recognition, meaning recognition, and meaning recall. Results indicated that participants in both the dual modality and single modality groups showed improved learning outcomes compared to the control group, highlighting the efficacy of pop songs in enhancing incidental vocabulary learning. However, dual modality input did not lead to significantly greater learning gains in any of the three dimensions of vocabulary knowledge compared to the single modality condition. These findings provide further insight into the impact of input modality on incidental vocabulary acquisition and offer pedagogical implications for optimizing incidental vocabulary learning outcomes using real-world resources.</p>