A vehicle occupant detection apparatus having a plurality of load sensors located to produce analog signals indicative of the presence/absence of a seat occupant and the type of seat occupant (adult or child), in which the analog signals are supplied to an occupant detection ECU to be converted to digital form and judged, and in which the occupant detection ECU and load sensors are powered by the same power supply, so that the accuracy of A/D conversion is unaffected by variations in supply voltage, and moreover only a single stream of encoded digital data, conveying seat status information, is supplied to an air bag control apparatus.