An autonomous bubble generating plasma unit for water treatment comprising: a first reactor and a second reactor; wherein the first reactor comprises: an insulating duct body, a first reacting water duct, a primary coil, a secondary coil wound around the first reacting water duct, a resonance generating part, a winding number adjusting bobbin, a resonance sensor and a static mixer; wherein the first reacting water duct has a duct body with a predetermined length, and the secondary coil is wound around said duct body, said duct body provided with the static mixer in the duct body; wherein an insulating duct body of a predetermined length is installed on the outside of the first reacting water duct excluding the resonance generating part, said resonance generating part provided on the outside of the secondary coil; wherein in the resonance generating part the primary coil is wound on a primary coil bobbin installed at a predetermined gap from the outside of the secondary coil, said secondary coil located in a water introducing part of the first reacting water duct; wherein the winding number adjusting bobbin is configured to adjust the number of windings of the primary coil wound on the primary coil bobbin to be a resonance point, wherein a motor drive for forward and reverse rotations is installed at the winding number adjusting bobbin, such that the winding number adjusting bobbin is controlled on the basis of resonance information applied to the secondary coil by the resonance sensor; wherein the second reactor comprises a second reacting water duct connected to the first reacting water duct to receive a supply of treated water treated in the first reacting water duct, said second reacting water duct provided as an insulating duct of a predetermined length; an internal electrode installed in the second reacting water duct and formed as a Kenics mixer-type structure; and an external electrode installed so as not to be conductive with the internal electrode and having a cylindrical mesh-type duct body. a first reactor and a second reactor; wherein the first reactor comprises: an insulating duct body, a first reacting water duct, a primary coil, a secondary coil wound around the first reacting water duct, a resonance generating part, a winding number adjusting bobbin, a resonance sensor and a static mixer; wherein the first reacting water duct has a duct body with a predetermined length, and the secondary coil is wound around said duct body, said duct body provided with the static mixer in the duct body; wherein an insulating duct body of a predetermined length is installed on the outside of the first reacting water duct excluding the resonance generating part, said resonance generating part provided on the outside of the secondary coil; wherein in the resonance generating part the primary coil is wound on a primary coil bobbin installed at a predetermined gap from the outside of the secondary coil, said secondary coil located in a water introducing part of the first reacting water duct; wherein the winding number adjusting bobbin is configured to adjust the number of windings of the primary coil wound on the primary coil bobbin to be a resonance point, wherein a motor drive for forward and reverse rotations is installed at the winding number adjusting bobbin, such that the winding number adjusting bobbin is controlled on the basis of resonance information applied to the secondary coil by the resonance sensor; wherein the second reactor comprises a second reacting water duct connected to the first reacting water duct to receive a supply of treated water treated in the first reacting water duct, said second reacting water duct provided as an insulating duct of a predetermined length; an internal electrode installed in the second reacting water duct and formed as a Kenics mixer-type structure; and an external electrode installed so as not to be conductive with the internal electrode and having a cylindrical mesh-type duct body.