ABSTRACT. – The Danube Delta Biosphere Reserve. Protection versus Human Impact. The total area of DDBR is of about 5,800 km2 more than half of which (3,510 km2) belong to what is commonly called the “Danube Delta” while the remaining area is  shared between the upstream Danube flood plain (Isaccea-Tulcea sector 102 km2), the Razim-Sinoie lagoon complex (1,145 km2), the neighboring strip from the Black Sea (1,030 km2) up to the 20 m isobath, and the Danube river between Cotul Pisicii and Isaccea (13 km2). The hydrological regime basically the water circulation, represents the vital component of the very existence of the delta space. Flooding is a normal event within the delta’s annual cycle and floods normally occur between April – June, when 33 % of the Danube’s annual flow may pour into the delta. The Danube Delta maintains its enormous biodiversity in a better state than most other deltas in Europe, even in the world.  It contains a greater range of habitat types, lower and higher plants, invertebrates and vertebrates than all other deltas in Europe. However, this mosaic of ecosystems, evolving under the direct action of the less polluted Danube waters, marine waters and the general factors of the climate, fell under the impact of human activity beginning with the first half of the 19th century when the Sulina Arm was corrected to facilitate the navigation of sea vessels. Subsequently, inland canals to increase fish productions were built (1910 – 1935), enclosures were created for agriculture, fish-farms were developed, reed and timber were exploited (1960 – 1989). The Ukrainain government is currently widening the Bistroe channel near Vîlcov to form a canal to the Black Sea. The possible dredging of the Ukrainian side of the Chilia arm of the river from Vilcov to Ismail would have very significant ecological implications for the Romanian sector of the Delta. Inside this territory, the Danube Delta Biosphere Reserve has structured the following areas: strictly protected zones – 18 (506 m3/sec); buffer zones (2,233 m3/sec) situated around the strictly protected zones in order to gradually reduce human pressure, and transitional zones (3,061 m3/sec) englobing all rural and urban settlements (the town of Sulina), and were traditional activities are currently practiced. The floristic and faunistic inventory will be enriched by ongoing research developed by specialist institutions under some profile programs, coordinated by the National Danube Delta Institute for Research and Development.