Problems of application of radar interferometry for digital elevation model constructing and displacements estimation of oilfields in West Siberia are examined and resolved in this article. Experience of study and adaptation of interferogram computation technique due to radar observation of area with difficult landscape (wetland, dense forest, peatbog) from the point of InSAR processing are summarized. Compare with geodesic survey results is conducted and estimation of applicability of InSAR technique is done.