1. An automatic analyzer comprising: a dispensing mechanism that dips a dispensing nozzle in a dispensing target contained in a container, aspirates the dispensing target, and discharges the dispensing target to a reaction container; a pressure sensor that detects pressure inside the dispensing nozzle of the dispensing mechanism; a storage unit that stores multiple items of determination-purpose reference data used in determining whether or not the dispensing mechanism is abnormal; a determination-purpose reference data selection unit that selects one item of the determination-purpose reference data from the multiple items of the determination-purpose reference data stored in the storage unit, based on the detection result from the pressure sensor when the dispensing mechanism dispenses a reference dispensing target configured to contain a known ingredient; and an abnormality determination unit that determines whether or not the dispensing mechanism is abnormal, based on the detection result from the pressure sensor and the determination-purpose reference data when the dispensing mechanism dispenses a dispensing target used in analysis.