Abstract: [Object] An object of the present invention is to provide a water treatment system capable of increasing the treatment rate by causing active species, such as radicals, produced by discharge to efficiently act on treatment water. [Solution] The water treatment system is characterized by including: at least a pair of cylindrical electrode 3 and a linear electrode 4 in a treatment chamber 2, the linear electrode 4 being disposed along the central axis of the cylindrical electrode 3; and treatment water mist supply means 7 for supplying treatment water in the form of mist composed of droplets having a particle diameter of 1500 ?m or less to a discharge space generated by applying a high voltage between the cylindrical electrode 3 and the linear electrode 4.