Three kinds of herbs Vetiveria zizanioides, Pennisetum purpureum Schum and Miscanthus floridulus were selected for an experiment of soil and water conservation in the red soil hilly region of Southern China. Observations of soil physiochemical properties, runoff and soil erosion were made in runoff plots for nearly three years. Results show that compared with Vetiveria zizanioides and Pennisetum purpureum Schum, Miscanthus floridulus has obvious advantages on increasing surface coverage, improving soil physiochemical properties, reducing and retaining surface runoff, improving micro-landform, controlling and reducing soil erosion, and improving ecological environment. Furthermore, Miscanthus floridulus are widely distributed, the seeds can be obtained easily, and the cost of planting is very low. Therefore, Miscanthus floridulus is a good grass for soil and water conservation. Miscanthus floridulus should be selected firstly in projects of soil and water conservation in the ed soil hilly region of Southern China.