Abstract: A system for testing and evaluating a device, such as a LSI device, by searching for a factor of defect of the device is disclosed, in which terminals are classified into a plurality of terminal types based on information related to various testing conditions, and data concerning the margin of the testing conditions is obtained by altering the testing conditions for every terminal type. Further, a factor of defect of a specific terminal type is searched for in accordance with the data concerning the margin of the testing conditions, and a defective terminal is detected from the specific terminal type. A method for testing and evaluating the device is also disclosed, which is executed by operating the system described above.