A sample, a reagent, etc. in a reaction container 132 is agitated with an ultrasonic wave generated from a piezoelectric transducer (141, 142). A power supply unit (144) applies, to the piezoelectric transducer, a voltage having been subjected to frequency modulation at frequencies over an optional frequency range. An analyzing section (130) measures a reaction product produced as an analysis target from the reagent, etc. and the sample under agitation, and then analyzes components of the sample. With such a construction, adjustment work needed in an agitating section can be simplified, and satisfactory analyzed results can be obtained regardless of differences in frequency characteristics of ultrasonic wave generators used for ultrasonic agitation.