There are many input parameters to control a DC-RF hybrid plasma flow system, such as total gas flow rate, central gas flow rate, swirl gas ratio, RF power and DC power. Furthermore, the interactive effects among these parameters should be considered. In the present study, statistical analysis using simple linear model is conducted to clarify the effects of the input parameters and their interactions on the outputs such as particle residence time and average temperature in a DC-RF hybrid plasma flow system. The thermofluid characteristics of a DC-RF hybrid plasma flow are compared with those of an RF plasma flow. It is shown that the plasma characteristics are changed drastically by adding even small DC power. Furthermore, controllability is also improved by optimizing the operating conditions of a DC-RF hybrid plasma flow system. (C) 2004 Elsevier Ltd. All rights reserved.