This document specifies the general requirements relating to the observation and evaluation method of railway subgrade (substructure and foundation ground) settlement and deformation for new-built railway and existing railway. (1) In Chapter “General Requirements”; the observation duration and interval of settlement/deformation, the instrument calibration, etc. are defined. The measurement conditions, the deformation monitoring network establishment, repeated survey, observation level, observation accuracy, observation path and other measurement- related technological requirements, as well as requirements on observation equipment, observation data processing, feedback of and countermeasures for settlement/deformation abnormalities and data abnormalities, are stipulated. (2) In Chapter “Observation schemes for subgrade”, the key points of the observation of the settlement/deformation of the earthworks are clarified, and the observation period, the observation cross-section interval, the observation point layout, the observation frequency, the starting time of the settlement observation as well as the cases where the observation frequency is increased or decreased are defined. (3) In Chapter “Observation prediction and evaluation”, the requirements on definition of evaluation section, method of evaluation, time and conditions for evaluation are specified; the influence factors that shall be considered in the evaluation are defined; the evaluation criteria, prediction and analysis of the settlement of the observation points, as well as settlement evaluation, are specified