This invention intends to reduce a time difference in information collection time as much as possible in a vehicle installed network system for collecting information on distributed positions within a vehicle. According to this invention, information on a measurement result by a sensor (23) at a time point after a previously-defined time elapses since a specified signal transmitted regularly is received is held in a sensor data storage register (49) on a network (21) installed within a vehicle, capable of broadcasting, achieved according to a communication method in which a transmission right is supplied regularly, and the information is transmitted at a time point when the transmission right is obtained on the network (21). In the vehicle installed network system for collecting information on the distributed positions within the vehicle, the time difference in the information collection time can be reduced as much as possible.