Abstract: Owing to the influence of uncertainties, the prediction of settlement after construction is inaccurate in the actual settlement monitoring. The predictability of the settlement time series is analyzed by using the recurrence plots and recurrence quantification analysis method. A settlement time series with high predictability is chosen to make an accurate prediction of settlement after construction. The predictability analysis of the non-ballasted-track integrated bed settlement time series show that (1) the settlement time series is chaotic; (2) the more regular of the color distribution and the more uniform in the shade, the smaller white areas appear along the main diagonal, and the stronger the predictability of settlement time series; (3) quantitative analyses of the recurrence plots on this basis may extract the recursive quantitative index curves over time and the immediate determining starting point of prediction time; (4) the recurrence plots are used to get the arbitrary entropy of the second order as the predictable time length of the settlement time series to comprehensively extrapolates the best settlement time of the forecast effect.