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The River Nemunas forms the large delta both in the territory of Lithuania and the Kaliningrad Oblast of Russian Federation. From the historical times the landscape of this transboundary region was developing under the different anthropogenic influence: establishing polder systems, channels for shipping, managing of agricultural land, excavating peat, constructing roads, building settlements, etc. In this study we focused on the less-disturbed landscape, its components of physical environment and status. Nowadays this transboundary region with older and newer parts of delta is extended within two administrative districts in 3056 km², 55.8 % of this belonging to Lithuania and 44.2 % to Russia. The compilation of statistical and research data on the area, landscapes and their components from two countries was made and supplemented with correlation-regression method and ArcGIS 10.2.1 program. Changes in physical environment were determined by 3 main components : 1) forested land area; 2) nature protected area; 3) changes in the quality of Nemunas delta surface water. The research has revealed, that during the last 25 years the physical environment of whole region has started to improve towards more sustainable status with gradual increase in landscape naturalness. These improvements are most evident in the west of the region: on Rusnė island and close territories, where Nemunas Delta Regional Park (Lithuania) is located. Here the diversity of preserved objects and increase in total nature protected area has been the greatest since 1992. In Slavsky district (Russia), where the increase in nature protected area was also fascinating from 1992 to 2004, a few reservations have lost their status. Forested land increased on the average by 3.6 % in the whole region from 1986-1997 to 2012. The improvement of the quality of Nemunas delta surface water was documented in both sides of the river: content of phytoplankton decreased by 30 % from 1994-2005 to 2006, and the newest data show the stabilisation trend. The annual concentration of phosphate phosphorus in the waters of delta decreased more than 80 % in 1997-2002 as compared with 1986-1991. However the latest data show the larger range of this element in separate years. [ABSTRACT FROM AUTHOR]