Heretofore, there has been demanded an automatic analysis apparatus which can prevent cross-contamination between reagents, which can prevent dust and gas from entering a reagent supply device, which can always know a remaining quantity of the reagent while can reduce the quantity of waste. According to the present invention, there is provided an automatic analysis apparatus in which a reagent supply device for supplying a reagent from a reagent container into a reaction container is removably attached to the reagent container, a protective door is provided in the reagent supply port in order to aim at preventing dust from entering the reagent supply device, and further the reagent container and the reagent supply device are provided with recording mediums for recording therein conditions thereof, a time of replacement thereof or the like, and which can inform whether the setting is proper or not.