In recent years, the civil aviation market has been impacted by the rapid development of China's high-speed railway. The competitive spatial distance between high-speed rail and civil aviation is explored through the application of the theoretical model related to the value of time. The competitiveness of civil aviation and high-speed rail is analyzed by establishing the relationship between the value of passenger travel time and the marginal time saving cost of civil aviation relative to high-speed rail, and the calculation model of marginal time saving cost is established, and the consumer groups corresponding to civil aviation and high-speed rail at different travel distances under different assumptions are observed by means of simulation. In general, with the change of passenger time value, the effective competitive space distance of HSR civil aviation is bounded by 800km, and its change is affected by the connection time of hub and operation speed, etc.