By taking the ecological slope protection of Ji'nan - Laiwu expressway located in the semi2arid region of middle Shandong Province as a research object,the vegetation restoration of rocky slope by external-soil spray seeding technique is investigated based on the ecological slope restoration observations.Results show that the succession process of secondary vegetation restoration is more rapid than natural vegetation restoration.By calculating and measuring the important value,niche breadth,and niche overlap of species,rocky slope has gradually evolved into the grass2shrub vegetation with importance value,such as alfalfa,tall fescue,amorpha,perennial ryegrass,and indigofera pseudotinctoria,which range from leguminosae grass to leguminosae and gramineae grass and from multi-grass type to grass-shrub vegetation.The weak competition among species for resources proves that plants during one and a half year's vegetation restoration period remain in the primary stage of succession process.