During the railways construction,such activities as subgrade building or tunnel excavating will induce soil and water loss, which has negative impact on eco-environment of the regions along the railway.The impact of soil and water loss for double-line-constructions of five railways in southeast coast of China was quantitatively analyzed and evaluated using the SWII method. The results showed that all the occupation land,impact area,and soil and water loss per kilometer for Fuzhou-Xiamen railway construction were the greatest in the five railways;the construction period of Wenzhou-Fuzhou railway was the longest and its proportion of uncontrolled area of soil and water loss per kilometer was the highest.The earthwork volume and wasted excavation per kilometer of Longyan-Xiamen railway were the greatest.The values for impact indices of soil erosion and water loss of Ningbo-Taizhou-Wenzhou railway,Wenzhou-Fuzhou railway,Fuzhou-Xiamen railway,Xiamen-Shenzhen railway and Longyan-Xiamen railway were 0.64,0.247, 0.375,0.265 and 0.64,respectively.The averaged value for these five railways was 0.278.