A plasma generating device provided with a plasma generating chamber (10) and a high-frequency antenna (1) arranged in the chamber (10) for generating inductively coupled plasma by applying a high-frequency power to a gas in the chamber (10) from the antenna (1). The antenna (1) is a low-inductance antenna formed of a first portion (11) extending from the outside of the chamber (10) into the chamber (10), and a plurality of second portions (12) diverging from an inner end (11e) of the first portion (11) in an electrically parallel fashion, and having a termination (12e) directly connected to the inner wall of the grounded chamber (10). The surface of the antenna (1) is coated with an electrically insulating material. Frequency of the high-frequency power applied to the antenna may be in a range from 40 MHz to hundreds of megahertz. The plasma generating device can generate desired plasma by suppressing disadvantages such as abnormal discharge, matching failure and others, and can be constructed so that a desired processing such as film deposition can be performed.