PURPOSE: To count living and dead cells, by making a cell suspension pass through pores of a detecting section to measure electric resistance or voltage.

CONSTITUTION: When a cell suspension 12 is sucked into a detecting section 1 with a pump 7 after the detecting section is immersed thereinto 12, cells 4 pass through pores 10. When cells 4 as dielectric pass, the resistance value between electrodes 3a and 3b increases only with the passage of a solvent of the suspension and voltage proportional to resistance is induced between the electrodes. It is found that the resistance value of dead cells becomes lower than that of living cells. So, thresholds V1 and V2 are set for a measuring section 9 to detect a voltage induced depending on dead and living cells, and when a detection voltage of a voltage detector 11 is between the thresholds, dead cells are determined to pass while living cells are done to pass when it is larger than the thresholds. Then, the suspension 12 is sucked at a fixed flow rate to be measured with a flow rate measuring section and the results are sent to the measuring section 9. Thus, living and dead cells can be identified and counted.