In the pressure control valve assembly according to the present invention, a plurality of communication passages or slits is formed in either the movable throttling plunger or its associated stationary seat portion, and such passages are so arranged that their effective communication area is variable with the plunger movement relative to the seat portion in the region where the plunger is positioned close to its full-throttling position, whereby throttling of the refrigerant gas in such a region is achieved through the effective communication area of these passages.