With the help of digital audio technology, fault diagnosis and quick identification of multi-channel synchronous vibration signals acquired from a triplex pump in well site were achieved. A characteristic model of fluid end’s vibration for this pump was established and further verified by indoor systematic experiments. The source of various vibration components was determined, statistic relationships between these components in different conditions were regressed, and typical sub-signals excited by pump valve movement were also modeled by the use of the basic operation unit segmentation and optimal frequency matching method. These works provide a favorable tool for identifying the pump vibration signals, fault diagnosis, and dynamic modeling of drilling reciprocating pump in future. Such results also have a good contribution to study vibration problems on other types of reciprocating machinery.