To provide a method and an apparatus for ship ballast water production which remove aquatic organisms in freshwater or seawater used as raw water by a method other than that of killing the aquatic organisms, and prevents the removed concentrate liquid of the aquatic organisms from being discharged to the outside of a system.

In the ship ballast water production method where the aquatic organisms in the raw water are concentrated and separated by passing the raw water through a separation membrane, and the membrane-treated water is used as ballast water, the concentrated and separated liquid is subjected to sterilization treatment.