A simple conductimetric method for measuring the hematocrit value of blood is described. Using a conventional electronic conductivity meter having a two‐electrode cell, the conductivity between the electrodes dipped in a diluted sample of the blood is measured and related quantitatively to the strength of suspended erythrocytes (that is, to the hematocrit value) in the test suspension. The extent of diluting the sample prior to the measurement is optimally determined on the basis of theoretical considerations. The merits of this instrumentation in terms of simplicity, economy, and linearity are compared with those of conventional methods of hematocrit determination. Possibilities of improving the present method by using inductive‐type conductivity meters and/or by using vhf (very high frequency) resonant circuit sensors are suggested. Relevant theoretical considerations and experimental results are presented.