To provide an effective purification method or purification system of shellfish.SOLUTION: A purification method of shellfish comprises the steps of: preparing seawater cleaned by applying ultraviolet rays, and containing bubbles of oxygen gas in a reservoir; maintaining the seawater in the reservoir while coming in contact with the shellfish; and deriving the seawater from the reservoir. The method is characterized in that the bubbles comprises ultra-fine bubbles of less than 100 nm in diameter, and the ultra-fine bubbles selectively adsorb and desorb virus accumulated in the shellfish. The purification system of the shellfish includes: an ultraviolet ray irradiation unit for purifying the seawater by the ultraviolet rays; an ultra-fine bubbles generation unit for generating the bubbles of oxygen gas of less than 100 nm in diameter in the seawater; an ultraviolet ray irradiation unit for purifying the seawater by the ultraviolet rays; and the reservoir connected to the ultra-fine bubble generation unit, and storing the seawater. The reservoir is characterized by holding the shellfish.SELECTED DRAWING: Figure 1【課題】効果的な貝類の浄化方法または浄化システムを提供する。【解決手段】貝類の浄化方法は、紫外線を照射して清浄化され、かつ酸素ガスの気泡を含有させた海水を貯留部に準備すること、前記海水を貝類に接触させた状態で前記貯留部に維持すること、前記海水を前記貯留部から導出することを含み、前記気泡は、直径100nm未満の超微細気泡を含み、前記超微細気泡が貝類に蓄積されたウイルス等を選択的吸着脱離することを特徴とする。貝類の浄化システムは、海水を紫外線により清浄化する紫外線照射部と、海水中に直径100nm未満の酸素ガスの気泡を発生させる超微細気泡生成部と、海水を紫外線により清浄化する紫外線照射部と前記超微細気泡生成部に接続され、前記海水を貯留する貯留部とを備え、前記貯留部は貝類を保持することを特徴とする。【選択図】図1