PURPOSE: To provide a gate valve in which stable sealing performance and operability can be maintained, even if the temperature and the heat transfer coefficient thereof are changed.

CONSTITUTION: When a valve element 5 is brought into contact with the valve casing 1 for closing the valve, divided valve elements 6A, 6B are partially deflected by the cutout parts 9A, 9B for absorbing the dimensional change in the valve casing 1 or the like, so that the valve closing operation and sealing performance can be always properly stabilized. When an opening operation force is given to the divided valve element 6A on one side through a valve stem 10, since the upstream flow passage A is communicated with the valve chamber 3 through a communicating passage 11. The differential pressure is not exerted on the divided valve element 6A, and only the frictional force due to the pressing action between the seat part and the divided surface becomes a sload. By the moving force of the divided valve element 6A, the divided valve element 6B is moved in the same direction through a connecting member 12. The deflection of the divided valve element 6B is already released, and only the frictional force due to the differential pressure on the seat part becomes a load. The movement in the direction of opening operation can be lightly and easily carried out, and the drawing-out force can be reduced.