Abstract: In a relief valve of the type including a main valve unit incorporating a main valve member (poppet) adapted for engagement with a cylindrical member and a pilot valve unit for controlling a fluid pressure whereby an inlet port of the main valve unit is communicated with a control chamber of the pilot valve unit by an internal pilot passage through a choke formed in a seat member of the pilot valve unit, the choke is formed with an expanded portion having a closed end and through holes for directly communicating the expanded portion with the internal pilot passage and/or the cylindrical member is composed of a unitary-construction member formed with a plurality of flow paths communicated with one another.