Task execution time prediction modeling is of great significance to the safety of special vehicle crew and maintenance of overall combat effectiveness. In our study, a task execution time prediction model for crew information processing task is proposed considering the characteristics of information processing task, as well as the interaction mode of man-machine system of special vehicles. In addition, a model validation experiment was conducted adopting 20 subjects facing to two kinds of representative tasks, and both of them have two levels of complexities. The result shows that there is a highly positive correlation (r = 0.999, p = 0.001) between the model prediction and the experimental results of four tasks, which indicates that the model has a good applicability. Based on the rationality of model validation, the application research of the model was conducted. The result shows that for the sub-tasks with more objects and visual searching difficulty, the speech interaction mode can reduce the operation duration to a great extent; for simple subtasks with less operation steps and strong coherence, the touch interaction mode has certain advantages.