Firstly,this article designed a data acquisition system based on LabWindows/CVI. The system combined service and client terminal. It used secondary thread of thread pool to acquire data and packed and transmitted data to client terminal in asynchronous timer. Secondly, this article discussed the influence of two different ways of data acquisition and dealt with invalidation of some Labels, which can provide reference for further using LabWindows/CVI to acquire data of ARINC429.