To improve reliability by integrating mechanisms of a dispenser and an agitator and reducing the number of component in an automatic analyzer for analyzing a biological sample such as an urea, a blood or the like an to reduce a cost.

The automatic analyzer of the type for analyzing by dispensing the sample and a reagent in a reaction container 6, agitating to mix them comprises an agitating motor head 3 at a sampling arm 1, an agitating arm turning mechanism and vertically moving mechanism also used as those of the sampling mechanism. In this analyzer, a cleaning water of the reaction container is poured by a reagent dispensing probe 2.