Abstract: This paper analyses the present situation of river silt delivery ratio, the delivery ratio change in time and space, and the development trend in South Shaanxi, indicates that under the spesific physical geography conditions, the tractional load ratio in the silt is rather great and it made the delivery ratio of this district less than 1. This is a very important character of river silt migration in South Shaanxi; the delivery ratio has an obvious difference in space; generally, it gets bigger along the river flow; considering the time, it has had the trend of decrease since the fifties, and in the coming days, with the decrease of river silt runoff volume and the manmade erosion worsening in this district, the silt delivery ratio will decrease further.