Aviation fuel may carry electrostatic charges during transportation, which may cause fires. Therefore, it is necessary to quickly measure the conductivity of aviation kerosene to avoid accidents. In this paper, a portable device that can quickly measure the conductivity of oil is produced by using the constant current source method, which adopts the design method of split design and compatible docking. The design of seperading the probe and body can measure the conductivity of tested oil with great accuracy. A set of testing experiments is conducted, and the results show that the device could effectively measure the conductivity of aviation fuel.