This paper describes a method of real-time obstacle avoidance for a car-type mobile robot. Car-type robots have an advantage in stability as the personal mobility, while specific features to car-type robots need to be considered in obstacle avoidance. They cannot avoid adjacent obstacles without the backward movement because they do not have a function to make a spin turn. In addition, there is fear that the accident will occur due to the difference between track followed by front and back inner wheels during turning. We developed a model method of obstacle avoidance that considered the unavoidable area and the track difference, and evaluated it using an actual car-type robot.