With the development of control technologies such as eye movement control, voice control, and gesture control, multi-modal human-computer interaction has become a leading development trend for future aircraft cockpits. However, current research on multi-modal interaction primarily focuses on comparisons between single-modal and multi-modal interaction, and the evaluation models are often conducted for a single-modal method. A com-prehensive ergonomic evaluation method for multi-modal interaction has not yet been developed. This research proposes an evaluation model for multi-modal interaction in aircraft cockpits, incorporating “Task Conflict Evaluation—Channel Conflict Evaluation—Channel Load Evaluation,” based on the analysis of pilots’ information cognitive processing. The model sequentially evaluates the workload of multi-modal interaction technology in aircraft cockpit scenarios from the perspectives of task level, channel occupancy, and channel resource demand. Validation experiments were conducted using route planning tasks, assessing the workload for tactile interaction modes and multi-modal interaction modes, and comparing them with subjective workload and behavioral performance to confirm the effectiveness of our evaluation model.