The electron temperature (T-c) in an electron cyclotron resonance plasma is clarified to depend on the spatial profiles of the microwave-power absorption by both the electromagnetic-waves measurement and the simulation of microwave power absorption. It is found that T-c is controlled by varying the magnetic field configuration and/or the microwave frequency since the power absorption profile is influenced by the effective resonance width. In fact, T-c is observed to decrease with decreasing the magnetic field gradient at the resonance point for N-2, Ar and O-2/Ar plasma. (C) 2003 Elsevier B.V. All rights reserved.