The invention provides a method for producing a logging neutron source. The method comprises the following steps: (1) after the first cycle of a reactor is shut down, taking out a primary neutron source, and placing the same in a shielding container; (2) transporting the shielding container to a logging base, and taking out a neutron source core block from the primary neutron source, and placing the neutron source core block at a lower end part of a logging device; (3) placing a lead layer and a paraffin layer above the lower end part of the logging device in sequence; and (4) fixing a detector above the paraffin layer, and packaging the logging device. In the method provided by the invention, the primary neutron source in the nuclear reactor is sued as the neutron source of the logging device, thereby not only solving the problem of radioactive-waste disposal in a nuclear power plant after the primary neutron source is taken out, but also effectively solving the problems of long half-life period and high cost of the Am-Be neutron source. In addition, the lead layer above the logging neutron source provided by the invention can shield gamma rays generated by the neutron source, andthe paraffin layer can slow down the neutrons scattered in the logging device toward the detector direction, thereby improving the safety of the logging device.