The invention discloses a combined unit used for drought-resisting sowing of dry land. The combined unit used for drought-resisting sowing of the dry land comprises components such as a furrowing blade, a hanging bracket, a main frame, a seed fertilizer box, a potato seed sowing mechanism, a potato seed box, a ridging scraper blade, a ridge shaper, a movable support, a film laminating wheel mechanism, a disc earthing mechanism, an L-shaped flexible rack, a film rolling support, a ground wheel, a transmission mechanism and a potato seed furrowing device. The combined unit used for drought-resisting sowing of the dry land has the advantages that firstly the combined unit can complete operations of furrowing, fertilizing, sowing, ridging, shaping, film mulching, film laminating, earthing and the like in one step in the field under the traction action of a tractor; secondly, a ridge film trench planting drought-resisting sowing dry farming planting mode is realized, the drought resistance and yield of crop are greatly increased, and a film saving effect is obvious; thirdly, the combined unit is designed into a two-station foldable rack, so that the transportation safety performance of the combined unit is improved; fourthly, compared with sowing machines of the same type at home and abroad, the combined unit used for drought-resisting sowing of the dry land is simple in structure, compact and flexible in type, low in cost and easy to manufacture, popularize and apply.