The present invention is to present a bacteria analyzer comprising: a detector comprising: a light source for irradiating light on a measurement sample prepared from a specimen and a reagent; and a light receiving unit for receiving light generated by irradiating the light on the measurement sample from the light source; a scattergram data acquiring means for acquiring scattergram data for generating a scattergram having information related to size of the bacteria contained in the specimen and fluorescence information generated by the bacteria as parameters; a bacteria number acquiring means for acquiring number of bacteria contained in a plurality of regions on the scattergram for each region; and a form determining means for determining a form of the bacteria contained in the specimen.