Provided is an analyzer capable of reducing the amount of wasted reagents and shortening time required for solution sending, thus increasing throughput for analysis. A microsyringe sucks a minimum required amount of reagent that is substantially the same amount of capacity of a flow cell to a sampling nozzle. Then, the sampling nozzle is inserted into an injection port of the flow cell, and the reagent is injected into the flow cell by driving the microsyringe. The inside of the sampling nozzle is cleaned by moving the sampling nozzle to the cleaning tank and ejecting cleaning water from the sampling nozzle, and the outside of the sampling nozzle is cleaned by spraying cleaning water from an inner wall of the cleaning tank.