Fluid control valve and mass flow controller

A fluid control valve configured to include a valve seat block and a valve element member, the valve seat block comprising:

• an in-valve flow path that is formed inside of the valve seat block;
• and a valve seat surface that is brought into contact with or separated from a seating surface of the valve element member, wherein
• the valve seat block further comprises:
• one end surface part that is at an upstream end of the in-valve flow path and formed with an inflow opening connected to an upstream side flow path;
• the other end surface part that is at a downstream end of the in-valve flow path and formed with an outflow opening through which fluid flowing in from the inflow opening flows outside the valve seat block;
• a protruded rim that is protruded by a predetermined height so as to surround the outflow opening in the other end surface part, and comprises a pressed surface that is pressed toward a one end surface part side during assembly;
• and
• a cutout that is formed in a part of the protruded rim so as to be communicatively connected to a downstream side flow path.