PURPOSE: To provide a plasma processing system in which the cost can be reduced and the efficiency can be enhanced while preventing generation of particles, allowing uniform plasma processing on a sample, and protecting the sample against metal contamination at the time of etching.

CONSTITUTION: The plasma processing system 10 comprises a plasma chamber 11 for generating plasma through the use of a microwave electric field and a magnetic field induced by an electromagnetic coil, and a reaction chamber 13 arranged with a sample stage 15 for mounting a sample S and separator 17 surrounding the sample stage 15, wherein the separator 17 is provided with one or more nozzle holes 17a and a reaction gas introducing part having a gas blow-out port is disposed on the peripheral wall 13c of the reaction chamber 13. A gas introduction nozzle 22 made of a plasma resistant material is inserted, detachably, into the gas blow-out hole through the nozzle hole 17a.