The electron energy distribution function (EEDF) in an argon planar inductively coupled plasma was measured by the method of laser Thomson scattering. In a low‐pressure discharge, a clear departure from a Maxwellian distribution function was observed; an unambiguous measurement of a non‐Maxwellian distribution in a low‐density glow discharge. The non‐Maxwellian EEDF became Maxwellian in a higher pressure discharge. These observations were attributed to the lack of randomizing collisions in the low‐pressure discharge and the increase in the number of these collisions at higher pressure. ©1996 American Institute of Physics.