This study investigates the temporal organization of prenuclear glides [j] and [w] in Hefei Mandarin using acoustic measurements. While the status of prenuclear glides in Chinese syllables remains debated, we employ a recently developed acoustic approach to analyze how CjV and CwV syllables are coordinated. Our results suggest that prenuclear glides in Hefei Mandarin are more likely to be part of the rime rather than forming complex onsets. The findings align with previous research on the status of Mandarin prenuclear [j] but reveal inconsistencies for prenuclear [w] compared to prior studies. This research contributes to our understanding of Chinese syllable structure and highlights the utility of acoustic methods in inferring abstract phonological structures.