There is provided a test apparatus for testing a device under test, including a signal supply section that supplies a test signal to the device under test via a transmission line, and a comparing and judging section that receives a response signal from the device under test via the transmission line shared with the signal supply section, and judges whether the device under test is acceptable by referring to a comparison result obtained by comparing a signal level of the response signal with a reference level corresponding to a logic pattern of the test signal.