Provided is an automatic analysis device that enables a reagent to be reliably loaded in and loaded out within a stipulated amount of time, even during analysis and without stopping the analysis, and that enables a reagent to be exchanged without causing a long wait for the operator. Provided is the automatic analysis device that comprises the following: a reagent cooling box that cools and holds a plurality of reagent containers, and that accommodates therein a reagent holder for movably holding the reagent containers which are inside the reagent cooling box and a reagent loader for loading the reagent containers into and out of the reagent cooling box by moving in a vertical direction with respect to the reagent cooling box; a reagent cooling box cover that covers the upper surface of the reagent cooling box and that has an opening through which the reagent loader can pass; an instruction means that provides instructions for the movement of the reagent loader; and a control device that includes, within the time of one cycle, a first time slot in which an operation for analysis is carried out and a second time slot in which an operation for the loading in or out of the reagent containers is carried out, and that executes control so that the reagent loader is not moved if the driving of the reagent loader was instructed by the instruction means in the second time slot.