The valve is the key part of filling and emptying system of ship lock. It is significantly affected by hydrodynamic load during operation，which can easily induce cavitation and vibration and threaten the safe operation of valve. When the filling and emptying valve in the emergency case of closing under hydrodynamic load，the water flow in culvert presents negative water-hammer waves，the pressure in front of the valve rises rapidly，while the pressure behind the valve drops sharply，and the working condition of the valve deteriorates. In this article，through the field-observation，the operation characteristics of the filling and emptying valve of the 4th gate on the north lane of the Three Gorges ship lock are monitored when it is closed in an emergency，including the change of flow rate and water level of valve well，characteristics of valve cavitation，flow-induced vibration and hoisting capacity. The response regularity of the maximum acting head when valve in the emergency case of closing under hydrodynamic load is analyzed.The result shows that the filling and emptying valve of the Three Gorges ship lock is safe and reliable under the emergency case of closing.