To deliver a liquid at high speed and with high accuracy. A device for delivering a fixed quantity of liquid, comprising a pump section for metering the delivered liquid to provide a desired amount consisting of a plunger chamber formed in a cylinder block, and a plunger reciprocating in the plunger chamber, a valve section for switching between liquid flow channels for suction and delivery, a reservoir section for reserving liquid adapted to communicate with the pump section depending upon the position of the valve section, and a delivery section having a delivery port for delivering liquid, the device being characterized in that the pump section and the valve section are disposed connected to each other and that the maximum advance position of the plunger is defined by a plane where the front end surface of the plunger contacts the valve section and pump section. The valve section is removably disposed in the pump section. The plunger chamber is made of a cylindrical chamber fitted in a hole formed in the cylinder block. The valve section is in the form of a switching valve provided with a valve block having a first flow channel communicating with a reservoir vessel and a second flow channel communicating with the delivery section.