The utility model relates to the field of electrical equipment malfunction detection, and especially discloses a detection and analytic system for a gas insulation composite apparatus shell vibration signal in service. The detection and analytic system is characterized by comprising an oscillating acceleration sensor (2) arranged on a GIS (geographic information system) shell (1), wherein a signal output end of the oscillating acceleration sensor (2) is connected with an upper computer (7) sequentially through a signal conditioning unit (4) and a signal acquisition unit (5), and the upper computer (7) can carry out detection and analysis on the received signal. The test proves that the system provided by the utility model can be adopted to carry out detection and analysis on the vibration signal of the GIS shell in service, the system adopts the oscillating acceleration sensor to carry out sensing on the vibration signal, the sensor closely clings to the GIS shell for measurement, and the normal operation of GIS is not affected; and the vibration signal sensed by the sensor can be sent to the signal acquisition unit through signal conditionings such as filtration and amplification, and then sent the upper computer to be collected and analyzed.