To provide a seawater supply pump apparatus with low cost, high reliability and corrosion resistance against seawater without using a special expensive pump and equipment.

This seawater supply pump apparatus is provided with seawater supply pumps 11, 11 with suction ports to which seawater supply pipes 101, 101 are connected; discharge pipes 16, 16 connected to discharge ports of the seawater supply pumps 11, 11; and a discharge header pipe 17. The seawater supply pumps 11, 11 are started to discharge the seawater flowing in from the seawater supply pipes 101 and to supply the seawater to a prescribed place through discharge piping 102 connected to the header pipe 17. A liquid contact part in contact with the seawater is provided with resin lining, and/or the liquid contact part is formed of a resin material.