The purpose of this puper is to adopt Virtual instrument technology to collect and handle the alternator property parameter. It discusses the data acquisition system，introduces the mehtod of the signal acquired of sensor in a realistic situation with an economical suitable principle, and selects the fitting and proper data acquisition card. Lastly, by using LabVIEW of the National Insturments Co，it acquires and displays wave forms of EFI engine sensors. The data acquisition system designed by LabVIEW has stable perofmrance, high accuracy, and a user-friendly interface. It fully embodies the advantages of a virtual insturment.