To supplement the subjective appraisal of seat comfort, a new instrument capable of quantitative measurement and real-time display of a seat load has been developed.The pressure detecting part comprises 300 small pressure transducers of disc type installed inside an automobile bucket seat. Highly sensitive semiconductor strain gages are used as pressure sensing elements.The outputs from sensors are displayed on a CRT device whose screen is crosshatched into 300 parts corresponding to each sensor. Pressure distribution on a seat is shown by the difference in brightness on the screen. Brightness modulation can be made in five stages or on continuous level.The outputs are recorded and reproduced by a data recorder. Equipressure contours can be plotted through a digital computer. Some of the vehicle test results are described.