An automatic analyzing device comprising: a retaining mechanism that retains a plurality of reaction cuvettes; a rinse mechanism configured to rinse the reaction cuvettes; a detergent feeding mechanism configured to feed a special detergent to the reaction cuvettes that have been rinsed by the rinse mechanism; a storage unit configured to store a use frequency of each reaction cuvette for a specific reagent item; a counting unit configured to count and store in the storage unit the use frequency of each reaction cuvette for the specific reagent item; a determining unit configured to determine whether the counted use frequency has exceeded a predetermined threshold N1; and a control unit configured to control the detergent feeding mechanism such that, in a case where the counted use frequency exceeds the predetermined threshold N1, the reaction cuvettes are soaked with the special detergent only for a period of time equal to or less than a value derived by multiplying a pipetting cycle time, which indicates a period when a sample is pipetted, by the total number of reaction cuvettes and a predetermined integer, wherein said integer is equal to or larger than 1, characterized in that the control unit is further configured to control the detergent feeding mechanism such that: in a case where the counted use frequency exceeds a predetermined threshold N2, which is larger than the predetermined threshold N1, the reaction cuvettes, which have exceeded the predetermined threshold N2, are soaked without assigning them a new measurement, even when there is a request for a new measurement, in a case where the counted use frequency exceeds the predetermined threshold N1, and is equal to or smaller than the prescribed threshold value N2, the reaction cuvettes, which have exceeded the predetermined threshold N1, are not soaked after the measurement, but they are soaked when there is not a request for a new measurement after those reaction cuvettes are measured. a retaining mechanism that retains a plurality of reaction cuvettes; a rinse mechanism configured to rinse the reaction cuvettes; a detergent feeding mechanism configured to feed a special detergent to the reaction cuvettes that have been rinsed by the rinse mechanism; a storage unit configured to store a use frequency of each reaction cuvette for a specific reagent item; a counting unit configured to count and store in the storage unit the use frequency of each reaction cuvette for the specific reagent item; a determining unit configured to determine whether the counted use frequency has exceeded a predetermined threshold N1; and a control unit configured to control the detergent feeding mechanism such that, in a case where the counted use frequency exceeds the predetermined threshold N1, the reaction cuvettes are soaked with the special detergent only for a period of time equal to or less than a value derived by multiplying a pipetting cycle time, which indicates a period when a sample is pipetted, by the total number of reaction cuvettes and a predetermined integer, wherein said integer is equal to or larger than 1, characterized in that the control unit is further configured to control the detergent feeding mechanism such that: in a case where the counted use frequency exceeds a predetermined threshold N2, which is larger than the predetermined threshold N1, the reaction cuvettes, which have exceeded the predetermined threshold N2, are soaked without assigning them a new measurement, even when there is a request for a new measurement, in a case where the counted use frequency exceeds the predetermined threshold N1, and is equal to or smaller than the prescribed threshold value N2, the reaction cuvettes, which have exceeded the predetermined threshold N1, are not soaked after the measurement, but they are soaked when there is not a request for a new measurement after those reaction cuvettes are measured. in a case where the counted use frequency exceeds a predetermined threshold N2, which is larger than the predetermined threshold N1, the reaction cuvettes, which have exceeded the predetermined threshold N2, are soaked without assigning them a new measurement, even when there is a request for a new measurement, in a case where the counted use frequency exceeds the predetermined threshold N1, and is equal to or smaller than the prescribed threshold value N2, the reaction cuvettes, which have exceeded the predetermined threshold N1, are not soaked after the measurement, but they are soaked when there is not a request for a new measurement after those reaction cuvettes are measured.