A new method of measuring the charge density on a dielectric surface has been developed. An electrode is vibrated in the surface field to produce a signal that is displayed on an oscilloscope, or measured with a VTVM. A bias is then applied across the vibrating and fixed electrodes sufficient to produce zero output signal. The value of this bias and a simple calculation yields the surface charge and its polarity. The method is simple, nondestructive, gives reliable results when compared with other techniques, and has few disadvantages. Measurements may be made at atmospheric pressure without fear of discharges at a wide range of surface‐to‐electrode gaps. The measurement of the surface charge is independent of circuit parameters.