An automatic analyzer that accurately detects dispensation abnormality in dispensation conditions with small suction quantities has a statistical distance calculation unit that calculates characteristic variables regarding a sucking operation in the first dispensation and calculates a statistical distance D from reference data to the characteristic variables extracted from a memory. A comparison unit compares the statistical distance D with a preset threshold value stored in memory and if the statistical distance D is less than the preset threshold value, the first discharging operation is performed. A controller judges whether a single-handed judgment based on a dispensation quantity condition of the second or subsequent dispensation is possible or not. If the single-handed judgment is impossible, reference data is selected based on a judgment quantity regarding the first dispensation. Whether the sucking operation in the second or subsequent dispensation is normal or abnormal is judged based on the selected reference data.