Seawater filter

The invention relates to a seawater filter, which comprises a shell and a filter cartridge, wherein the shell is in a barrel shape, an opening is formed at the upper end of the shell, and the lower end of the shell is sealed; the columnar filter cartridge is inserted into the shell from the opening end at the upper end of the shell, and nonmetal insulating layers are arranged at the joint between the opening end at the upper end of the inside of the shell and the upper end of the filter cartridge and at the contact position of the bottom end of the bottommost end of the inside of the shell and the bottom end of the filter cartridge; and the filter cartridge and the inside of the shell are separated and kept from contact by the arranged nonmetal insulating layers, so an electrical contact reaction and a potential difference reaction are reduced, corrosion is prevented, and the service life of the filter cartridge and the shell is prolonged. In addition, the filter can buffer impact between the filter cartridge