A two-port valve includes a valve part configured to open and close a valve seat in a liquid flow path connecting a first port and a second port by a valve member and a pilot-type valve driving mechanism to open and close the valve member through a rod. The rod passes through an insertion hole of a plate facing on the liquid flow path in a sealed state. The valve member is provided to the tip part of the rod and also a cap which abuts against the periphery of the insertion hole of the plate when the valve member opens the valve seat and prevents intrusion of foreign material in the liquid into the insertion hole is provided to the rod.