The electrical generator of certain device is the power source for the servo system and other electrical systems. Traditional detection methods for the electrical generator usually need to buy or manufacture a great deal of special device. Some items are in fact very difficult to carry out, and the operation processes are complicated, with low automatization degree. In this article, the hardware and software design projects based on VI (Virtual Instrument technology) of the detection system are deeply researched based on LabVIEW, electrical parameter detection technology and serial port communication technology. In the hardware system, the intellectualized electric quantity detection modules are used as the isolation and adjustment units, making the cost low and the security high. The serial port transport of RS485 to RS232 is used for the data communication with general computers. In the software system, Lab VIEW is used as the developing platform. The data acquisition for the detection is designed based on the general serial port driver program in LabVIEW system. The signals are saved as data log files of LabVIEW. During the detection process, the data are monitored at the same time. Detection data are reported out as EXCEL files with ACTIVEX technology. The detection system can greatly develop the detection efficiency for the electrical generator of this device, and also reduce the developing cost for detection system.