A method for increasing the crop yield and planting efficiency in a heavy saline-alkali land comprises the following steps of: planting technologies of a pioneer crop of oil sunflower: building a raised field, desalting soil, covering the soil with a mulching film, uncovering the soil at strip-shaped intervals, applying conditioning agent, fertilizing and sowing, fixing seedlings and weeding, intertilling and hilling, removing superfluous discs and nutrient-free leaves, harvesting at the right time, and rotating crops; planting technologies of later crop of cotton: desalting the soil, coveringthe soil with a mulching film, uncovering the soil at strip-shaped intervals, applying conditioning agent, fertilizing and sowing, fixing seedlings, harvesting, and rotating crops. By using the method, the yield of the oil sunflower and cotton in the heavy saline-alkali land is obviously improved compared with the prior art, the dosage of the fertilizer is greatly reduced, the fertilizer utilization rate is improved, the fertilizer loss is reduced, the soil fertility of the saline-alkali land is obviously improved, and the nutrient and salt are balance are coordinated. Besides, the method makes full use of the phonologies and natural resources such as natural light, heat, rainfall, underground salt water and saline-alkali soil and the like, and avoids harmness and gets benefits, and realizes the green development and the low-carbon cycle of the barren and heavy saline-alkali land.