It’s very necessary to seek a way of the shortest path for ambulance dispatch in the 120 emergency command system. Based on the research on the application of quantum computing theory in the ant colony algorithm, this paper sets up an optimization mathematical model of a city's ambulance dispatch, uses a hospital and actual latitude and longitude of several crossroads in Xi’an to simulate ambulance passing in first aid, and gives pages for optimal dispatch process to display the dynamic state of ambulance. Through simulation and theoretical research, it is proved that this approach effectively solves the shortest path problem in the ambulance dispatch in case of presented several paths.