Several methods have been proposed for investigating complex traffic flows. However, the dynamics of vehicles and their drivers' characteristics, which are important factors for any traffic flow analysis, have not been considered sufficiently enough in the past. This paper describes a new concept for simulating complex traffic flows by multiple agents. The agents are considered as a kind of artificial life (A-Life), and their behaviors are independently based on their own knowledge. Drivers, vehicles, roads, and the traffic environment, which are essential elements in our simulation, are defined as the agents. The combination of the driver agent and the vehicle agent work based on the drivers' fields of vision and their unique individual characteristics. The road agent communicates with the vehicle agent in regard to its velocity and position. The effectiveness of our new method for modeling a traffic flow is shown by a simulation study.