Substrate treating systems are disclosed. The system may include a chamber with a processing space, a supporting unit provided in the processing space to support a substrate, a gas supplying unit provided in the processing space to supply gas into the processing space, a plasma source unit generating plasma from the gas, and a liner unit disposed to enclose the supporting unit. The supporting unit may include a supporting plate supporting a substrate. The liner unit may include an inner liner enclosing the supporting plate and an actuator vertically moving the inner liner.