To provide a simple reagent injector that is convenient for use, capable of injecting a reagent into a well and capable of moving the well, with a single manual operation.

This reagent dispenser is provided with a mounting table 5 for mounting a container 6 storing the reagent, a push pump 7 for discharging the reagent from the container 6 via a delivery nozzle 8, a pusher comprising an operation lever 25 or the like capable of pressing-operating the push pump 7, a slide table 4 for supporting a plate member arranged with the wells under aligned conditions, and a moving means for moving the slide table 4 along the advancing direction of the wells corresponding to one pitch, and the push pump 7 is pressed by the pusher to dispense the reagent, and to move to the next well.