Car- telematics is the most promising field of mobile communication. This paper focused on an interactive information system to use while driving a car. In experiments by using a driving simulator, the followings were investigated: situations where the driver can receive simple information such as weather forecasts and news, the allowable delay time of waiting for the information requested, and the driver's ability to understand the information supplied, while driving a car. The results obtained showed that the driver could receive the information under the situations of driving on a straight road and stopping at a red signal, that the driver allowed the delay of the requested information up to 4.5 sec, and that the driver could easily understand the contents of the supplied information that contained within about ten keywords. Also, as presentation of weather forecast on a car monitor, the most preferable presentation is "Expression method where the content was shown by white Japanese syllable characters in color back ground" . Topic A12