A two-dimensional fluid simulation of argon plasma in an electron cyclotron resonance source was performed and an experiment was conducted to compare the theoretical prediction and experimental measurements. Conservation equations for mass, momentum and energy in a multicomponent system were solved based on the finite element method in order to compute the fluid velocity field, pressure field, neutral species densities, charged species densities, and electron temperature. By using a Langmuir probe, the variations of electron temperature and electron density along chamber axis were measured fur pressures in the range 0.4-7 mTorr. Simulation results agreed favorably with experimental data.