Based on labVIEW development platform and Yanhua PCI-1711L data acquisition card, the diagnosis and testing system of hardware malfunction for crankshaft dynamic balancing machine was established. The real-time acquisition, displaying and saving of the vibration and rotating speed signals were completed, and also the data was processed and analyzed. Study on the RZW-100B horizontal dynamic balancing machine with universal joint indicates that this testing system has simple structures, flexible extensions, high practicability and high reliability, and its ratio of performance and price is also higher, providing new methodology for crankshaft dynamic balancing machine.