Abstract: reasonably. The use of JSY341-115 slant-hole packer and hydraulic centralizer in the separate injection pipe string has solved the non-centered problem of packing element of the conventional packer in the slant hole or in the horizontal well. The use of hydraulic pulling and running principle in the operation of nozzle of water injection mandrel has solved the technical problem of difficult pulling and running of nozzle in the directional well. The anchoring or set to the artificial bottom hole of the separate injection pipe string has solved the creep of the pipe string resulted from the unstable water injection pressure. The test of the actual working condition of individual layer, that is, the test of water injection amount and pressure of individual layer, has been realized by means of separate layer test.