Cognitive presence is essential for deep and meaningful learning, yet developing it poses challenges. Theoretically, peer-led teaching presence can enhance cognitive presence, but research on this facilitation is limited. This study used behavioural sequence analysis to investigate how peer-led teaching presence promotes cognitive presence development. First, the study found that peer-led teaching presence promotes overall cognitive presence development by facilitating transitions from the triggering event to the resolution stage via multiple pathways. It also facilitates transitions from lower-order learning (including the triggering event to exploration, exploration back to the triggering event, and the self-reinforcing cycle of exploration) to higher-order learning in the integration stage. Additionally, it breaks the cycle of triggering new events or self-circulation from the integration stage, ensuring a smooth transition to the resolution stage. In the exploration phase, peer-led teaching presence significantly increases exploratory behavioural sequences and promotes bidirectional transitions between these behaviours. Notably, it also increases a significant bidirectional triggering of divergence in the exploration stage and connecting ideas, synthesis in the integration stage. Within the integration phase, there is a marked increase in integrative behaviour sequences, enabling multiple routes from the integration to the resolution stage. Based on these findings, we propose practical implications are.