Abstract: Aiming at the sealing failure of the bayonet type fluid connector when the maximum work flow is exceeded, the failure mechanism of the product is analyzed theoretically in this paper. The flow impact test of the bayonet fluid connector is carried out and the failure flow value and failure mode of bayonet type fluid connector are obtained. The result shows that failure flow values are all greater than the maximum work flow at a specified flow rate of 5 m/s, which verifies that the maximum work flow specified by bayonet fluid connector is safe and reliable. At the same time, through comparative analysis of numerical simulation and test, it is concluded that the pressure difference and the maximum flow velocity of bayonet fluid connector under the failure flow mainly concentrate on the O-ring on the plug internal sealing block and the O-ring on the socket internal sealing rod, which verifies the consistency of simulation results and failure mode. The research shows that the failure mode of O-ring coming out of bayonet fluid connector can be predicted by numerical simulation.