The design and construction situations of A14 testing section soft soil roadbed on Qinhuangdao-Shenyang passenger transport special railway line are introduced. The subsidence data are observed in the testing sections what were treated through different groundwork treatment measures. The soft soil roadbed subsidence feature is discussed; and the subsidence data and subsidence rate after engineering works are predicted in the roadbed after consolidation treatment according to test data. The relationship between soft soil groundwork treatment measures and subsidences is also analyzed. The researching results indicate: the soft soil roadbed subsidence is affected by the added load very much; the subsidence amount of soft soil roadbed what is treated with gravel piles or lime injected piles is less than other methods of treatment; it is not a key that the rate of filling soil is controlled in the loose and soft soil roadbed.