Аннотация:In the last 30-40 years, the water runoff, sediment yield and heat flux of the Lena River has undergone significant changes due to, mainly, climatic factors (Fig.1, 2, 3). Features of hydrological changes on the marine edge of the Lena River Delta are slightly different than in the river. The reason is the transformation of runoff in the large and multi-branched delta. New data and methods allowed not only to clarify the values of water flow, suspended sediments and heat runoff at the closing gauge of the Lena (gauge Kyusyur), but also to estimate the river runoff into the sea (Table 1). Features of long-term and annual fluctuations of water flow, sediment yield and heat flux of the Lena River, their causes have been studied in detail. The role of anthropogenic factors was evaluated. New data about the current distribution of water flow and suspended sediments between the main deltaic branches, its long-term changes, about character of the flooding the upper part of the Lena River delta during spring flood are listed in the report (Fig.4). The analysis of the accuracy of the stationary hydrological observation data was performed. The possibilities of satellite imagery to study changes in temperature and turbidity of water in the river mouths are shown. The studies were performed due to RSF (No.14-37-0038).