Soil erosion is a natural geomorphic process on slopes in semiarid region, which influences the soil water holding capacity, nutrients stored and the plant species distribution. The hill-gully Loess Plateau is located in the forest-steppe region and has a semiarid climate with severe soil erosion. Vegetation is identified as the essential and available approach to control soil erosion and to recover degraded ecosystem. Diaspore is the base of vegetation regeneration and recovery after disturbance. Unfortunately, in the degraded ecosystem, diaspore is always regarded as a limited factor of vegetation regeneration. Especially, in eroded environments, seed limitation is caused not only by seed production reducing due to the soil degradation, but also by other seed ecological process. Diaspore morphology is one of the most important functional characteristics of plant, which influences seed production, seed dispersal, seed longevity, seed germination, seedling establishment, then influences species distribution and community composition. Many ecologists have studied seed mass, seed shape, and the corresponding ecological function. However, there are few studies on diaspore morphology and ecological function carried out in the hill-gully Loess Plateau region. 80 species were chose to investigate their diaspore morphology and distribution characteristics, in order to better understand the influence of diversity and adaptation of diaspores on plant restoration. Diaspores of the 80 species were collected from three small watersheds of Xinzihe watershed. To determine species distribution (species density and frequency) on eroded slopes in the study area, 304 quadrats of 69 sample plots from 16 eroded slopes were investigated. The results showed the mean seed mass varied widely (0.020-357.428 mg), with the mean mass of the heaviest diaspore (Ziziphus jujuba) was 17870 times higher than the smallest diaspore (Artemisia scoparia). The mean diaspore mass of most plant species were varied from 1.000 to 9.999 mg, occupied 52.5% of the study species. The Flatness Index of diaspore ranged from a value of 1.06 for spherical shape to greater value of 12.93 for spindle shape, with most of diaspores had the approximate spherical shape (61.3%). Diaspores of 33 species had appendages, such as pappus, awn, wing, spine, etc. About 87.5% species had emblazonry on the surface of diaspore. The main colours of diaspores among these species were brown and black. The diaspores of six species had the ability to secrete mucilage in contact with water. The relationship between diaspore mass and species density and frequency were negative, as well as the relationship between diaspore shape (FI) and species density and frequency were negative. The species with small diaspore, or the approximate spherical diaspore, or with the appendages such as awn, wing and pappus on the diaspore, or with the diaspore that can secrete mucilage distribute widely in the study region. These morphological traits of the diaspore have important role in the distance dispersal, adhering to the soil and persisting in the eroded habitat. And then help the species to adapt the drought and erosion. Diaspore morphological characteristics of adapting the drought and erosion are useful to guide the species selection of revegetation by seed addition.