More and more importance has been attached to inductively coupled plasma (ICP) in semiconductor manufacture. For a deep understanding of the plasma discharge process in the etching reactor, this study made a three-dimensional simulation on the Ar plasma discharge process with the commercial software CFD-ACE, which is according to the real experiment conditions and data supplied by North Microelec-tronic Corporation. The error of the simulation results is in the range of ±20% with credibility. The numerical results show that the three-dimentional spatial distribu-tion of electron density is reduced from the chamber center to the wall. The distri-bution of electron density, electron temperature and power deposition is related to the shape and placement of the coil. More and more importance has been attached to inductively coupled plasma (ICP) in semiconductor manufacture. This study made a three-dimensional simulation on the plasma discharge process with the commercial software CFD-ACE, which is according to the real experiment conditions and data supplied by North Microelec-tronic Corporation. The error of the simulation results is in the range of ± 20% with credibility. The numerical results show that the three-dimentional spatial distribu -tion of electron density is reduced from the chamber center to the wall. The distri-bution of electron density, electron temperature and power deposition is related to the shape and placement of the coil.