PXI (PCI eXtensions for Instrumentation) is an industrial standard platform derived from CompactPCI. The traditional Compact PCI platform extended the PCI Bus used in standard PCs to the one suitable for IPC with endurance of high temperature and shaking. Besides featuring in modularized instrumentation, open architecture and hot-swap functionality, the PXI is also equipped with high-speed network transmission, built-in counter and simultaneous triggered data transmission interface. The test instruments and systems implemented with these features can be integrated to PXI test systems easily due to compatible software and hardware technology. Replacing the single unit with modularized cards and chassis with traditional system, the device space is greatly condensed and the measurement functions are more diversified. The flexible structure and high performance/low cost advantages are most adequate to the frequent upgrade electronic products with short life cycle. Nowadays, the PXI systems have been successfully and extensively applied to testing in the automotive testing, semiconductor testing and aviation applications.