To ensure uniformity and rapidity of the treatment by highly dense plasma by providing a uniform plasma distribution in a chamber.

In the plasma treatment device comprising the chamber 2 with a substrate 10 accommodated therein and a plasma source 3 which emits the columnar free-standing plasma P in the chamber 2 and performs the plasma treatment on the substrate 10 by the plasma P emitted in the chamber 2, the substrate 10 can be disposed around the columnar plasma P in the chamber 2.