The current evaluation system of track geometry provides supervision of standards for graduation of the gauge and speed limits at excess of allowable values. At present maximum graduation of the gauge normalized in accordance with the standard operating Procedures for the current maintenance of railway track. This article discusses the shortcomings of the existing system of evaluation in terms of lateral track geometry. In order to overcome it, direction of improving current standards for estimating lateral track geometry is proposed and justified.On the basis of data on the track geometry parameters obtained from track measuring cars the analysis of interdependencies of lateral irregularity parameters for outer and inner rails in the curve was made using of the mathematical description of the parameters of rails lateral irregularities by identifying the length, amplitude and half-wave graduation. The presence of significant differences in the position of rails in the direction of the curves and larger lateral irregularities on the inner rail was estimated. The presence of patterns of length changes, amplitude and graduation of lateral irregularities is shown. Authors present results of the analysis of correlation parameters of lateral irregularities on the outer and inner rails in curved sections of the track. The presence of an average degree of correlation relationship of position of lateral position of outer and inner rails of curved sections is shown. The influence of the graduation of lateral irregularities on performance of rolling stock dynamics is given. Values of the graduation of lateral irregularities, unacceptable in terms of traffic safety, are established.