An automatic analyzer which is capable of detecting a dispensing abnormality with a high degree of accuracy without causing the decrease in the determination performance or the increase in the calculation amount caused by the configuration balance of the reference database is implemented. A dispensing nozzle of a sample dispensing mechanism 50 is immersed in a dispensing target contained in a specimen container 11 and sucks the dispensing target, and internal pressure of the dispensing nozzle of the sample dispensing mechanism 50 of ejecting the sucked dispensing target to a reaction container 41 is detected through a pressure sensor 54. A plurality of feature quantities are extracted from a waveform of the detected pressure, and a determination result is output through a linear combination formula using an optimal coefficient for a determination function that receives a plurality of feature quantities and outputs one value. The determination result indicates whether or not dispensing of the sample dispensing mechanism 50 is performed normally in accordance with the magnitude of the output result of the determination function.