Research conclusions: (1)In the settlement computation of bridge pile foundation in collapsible loess zone，the influence of negative friction resistance should be considered．(2)In design，it is reasonable that the total settlement of not more than the specified value is adopted for controlling the settlement of bridge pile foundation．(3)For the bridges in collapsible loess zone along the railway from Sanmenxia to Linbao，adopting the modified code of railway bridge to compute the total settlement of pile foundation can control the design．(4)The modulus of compressibility of soil beneath the pile bottom is the main influence factor on settlement computation，so it must be preciously measured during prospecting．