PURPOSE: To enable a test of industrial meter and to reduce the times for measurement and testing by allowing to have various input and output signals in one testing apparatus for industrial instrument.

CONSTITUTION: Each signal from an electrical signal measuring part 1 and an air pressure signal measuring part 2 is changed over by a multiplexer 3, converted from analogue value to digital value by an A/D converter 4, and is fetched in a CPU6 through an interface 5. A memory 7 is used for performing various arithmetic controls by the CPU6. Signals outputted from an electrical signal generating part 10 and an air pressure signal generating part 11 are converted from digital value to analogue value by a D/A converter 8 through the interface 5 from the CPU6, changed over and selected by a multiplexer 9, and outputted from either of the generating parts. Keys for inputting while assigning measurement or generation and keys for setting a classification of signals such as electrical signal and air pressure signal are provided at a setting part 14, in addition to a display part 12 and a printing part 13.