A rinse mechanism rinses reaction cuvettes with first and second detergents. An R1 reagent pipetting mechanism 8 rinses the reaction cuvettes that have been rinsed by the rinse mechanism with a special detergent. A counting unit counts and stores in a storage unit a use frequency of each reaction cuvette for a specific reagent item. A determining unit determines whether the counted use frequency exceeds a predetermined threshold N1. A control unit controls the R1 reagent pipetting mechanism such that, in a case where the counted use frequency exceeds the predetermined threshold N1, the reaction cuvettes, which have exceeded the predetermined threshold N1, are soaked with the special detergent only for a period 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.