An automatic analyzer comprising: a sensor configured to measure a liquid amount of a container containing liquid; a flow path system; a liquid discharging unit configured to discharge liquid from the flow path system; a syringe that is connected to a branch portion of the flow path system and configured to change an internal pressure of the flow path; and a controller , wherein the flow path system includes a first flow path , a second flow path , a first electromagnetic valve , and a second electromagnetic valve , the first flow path ranging from a nozzle to the branch portion , the nozzle aspirating or dispensing liquid from or to the container , the second flow path ranging from the branch portion to the liquid discharging unit , the first electromagnetic valve being provided on the first flow path and opening and closing the first flow path , and the second electromagnetic valve being provided on the second flow path and opening and closing the second flow path , and the controller is configured to operate the syringe , the first electromagnetic valve, and the second electromagnetic valve such that a predetermined aspirating, dispensing and discharging liquid operation is performed in the container , the liquid discharging unit , and the flow path system and wherein the controller is further configured to determine whether or not an abnormality occurs in the flow path system based on a difference between a. a predetermined threshold or a liquid amount measured by the sensor before the predetermined aspirating, dispensing and discharging liquid operation, and b. a liquid amount measured by the sensor after the predetermined liquid aspirating and discharging operation. a sensor configured to measure a liquid amount of a container containing liquid; a flow path system; a liquid discharging unit configured to discharge liquid from the flow path system; a syringe that is connected to a branch portion of the flow path system and configured to change an internal pressure of the flow path; and a controller , wherein the flow path system includes a first flow path , a second flow path , a first electromagnetic valve , and a second electromagnetic valve , the first flow path ranging from a nozzle to the branch portion , the nozzle aspirating or dispensing liquid from or to the container , the second flow path ranging from the branch portion to the liquid discharging unit , the first electromagnetic valve being provided on the first flow path and opening and closing the first flow path , and the second electromagnetic valve being provided on the second flow path and opening and closing the second flow path , and the controller is configured to operate the syringe , the first electromagnetic valve, and the second electromagnetic valve such that a predetermined aspirating, dispensing and discharging liquid operation is performed in the container , the liquid discharging unit , and the flow path system and wherein the controller is further configured to determine whether or not an abnormality occurs in the flow path system based on a difference between a. a predetermined threshold or a liquid amount measured by the sensor before the predetermined aspirating, dispensing and discharging liquid operation, and b. a liquid amount measured by the sensor after the predetermined liquid aspirating and discharging operation. a. a predetermined threshold or a liquid amount measured by the sensor before the predetermined aspirating, dispensing and discharging liquid operation, and b. a liquid amount measured by the sensor after the predetermined liquid aspirating and discharging operation. <EOS>