AUTOANALYZER

PROBLEM TO BE SOLVED: To provide an autoanalyzer of which the detergency of an analysis unit which contacts a sample or reagent can be improved.SOLUTION: An autoanalyzer includes: a pump 42 which feeds cleaning fluid for cleaning a sample dispensation probe from an accumulation tank 41; a tank 43 provided with a first opening 431 in which the cleaning fluid flows, a second opening 432 from which the supplied cleaning fluid flows out, and a third opening 433 which communicates with the atmosphere, and of which except the first and third openings 431 and 433 is closed; an on-off valve 44 which opens/closes the third opening 433; and a cleaning tank 45 provided with a discharge opening 451 from which the cleaning fluid flown out from the second opening 432 is discharged, opens the third opening 433, and stops flow-in of the cleaning fluid from the first opening 431 when the cleaning fluid in the tank 43 is higher than predetermined height H while cleaning of the sample dispensation probe is stopped.