To provide an ocean deep water collecting device suppressing a temperature rise in pumping up low-temperature ocean deep water.

This ocean deep water collecting device is constituted of a main pipe body 2 for pumping up the deep water and an auxiliary pipe body 4 externally fitted around the outer circumferential part of the main pipe body 2 so as to have an annular space part 3. The low-temperature ocean deep water pumped up by the main pipe body 2 is taken by an intake pipe 7A of an intake device 7 provided in the upper part of one end side of the main pipe body 2, and part of the ocean deep water is made to flow into the annular space part 3 between the main pipe body 2 and the auxiliary pipe body 4 via a deep water supply pipe 9 branched from the intake pipe 7A so as to suppress the temperature rise in the ocean deep water in the main pipe body 2.