Differential SAR interferometry has proved to be of remarkable potential for large-scale deformation

monitoring. However, a full operational capability has not yet been achieved due to atmospheric disturbance and

phase decorrelation phenomena. This paper deals with the main techniques for the application of InSAR to surface

deformation monitoring. Such techniques as the conventional SAR interferometry, Stacking Interferograms, Permanent

Scatterers Inteferometry and Corner reflector InSAR are presented in this paper， with their advantages and

limitations analyzed separately. The method for differentiating the atmosphere disturbance phase from the

deformation phase and the algorithm for identifying coherent point and spatial phase unwrapping based on Dealaunay

triangle network are discussed. From the viewpoint of practical application, the accuracy, precision and

reliability of D-InSAR measurement are analyzed. The key problems in the spatial integration processing of

multiple SAR images and the phase regression in the temporal domain of large coverage deformation mapping are also

studied.