A particle image analyzing method, comprising: detecting particles flowing through a flow cell; determining from a particle detection signal obtained whether desired particles are to be imaged, and then acquiring images of the desired particles; storing an acquired overall image of a sample into an overall-image memory; extracting particle components contained in the sample, and the number of the particles, from the acquired overall image of the sample; analyzing the extracted particle components in accordance with feature parameters, then after classifying the particle components according to the kind of component, computing respective concentrations of the classified components, and storing the classified components with the computed concentrations into a cropped image memory; displaying on display means the overall image stored in the overall-image memory; and in accordance with to-be-added or to-be-changed particle component information entered from operating means, conducting modifications and concentration-modifying computations upon the components stored in the cropped image memory, characterized by further comprising: setting up a plurality of particle detection conditions each different from particle detection conditions used as an image acquisition trigger; counting the number of particles detected independently under each of the conditions; and in accordance with either the detection counts under each of the detection conditions, or a difference or ratio between the detection counts, determining whether the acquisition of overall images is to be executed and how many images are to be acquired, or whether the acquired overall image is to be stored into the overall-image memory and displayed. detecting particles flowing through a flow cell; determining from a particle detection signal obtained whether desired particles are to be imaged, and then acquiring images of the desired particles; storing an acquired overall image of a sample into an overall-image memory; extracting particle components contained in the sample, and the number of the particles, from the acquired overall image of the sample; analyzing the extracted particle components in accordance with feature parameters, then after classifying the particle components according to the kind of component, computing respective concentrations of the classified components, and storing the classified components with the computed concentrations into a cropped image memory; displaying on display means the overall image stored in the overall-image memory; and in accordance with to-be-added or to-be-changed particle component information entered from operating means, conducting modifications and concentration-modifying computations upon the components stored in the cropped image memory, characterized by further comprising: setting up a plurality of particle detection conditions each different from particle detection conditions used as an image acquisition trigger; counting the number of particles detected independently under each of the conditions; and in accordance with either the detection counts under each of the detection conditions, or a difference or ratio between the detection counts, determining whether the acquisition of overall images is to be executed and how many images are to be acquired, or whether the acquired overall image is to be stored into the overall-image memory and displayed. setting up a plurality of particle detection conditions each different from particle detection conditions used as an image acquisition trigger; counting the number of particles detected independently under each of the conditions; and in accordance with either the detection counts under each of the detection conditions, or a difference or ratio between the detection counts, determining whether the acquisition of overall images is to be executed and how many images are to be acquired, or whether the acquired overall image is to be stored into the overall-image memory and displayed.