The phenomenon of functioning of fortified settlements of late Bronze Age and early Iron Age in northern Podlasie (North-Eastern Poland) is a relatively new research problem, on which the knowledge is a result of research conducted in the last several years. The aim of the paper is to present the preliminary results of the interdisciplinary research of the Jatwieź Duża site (district of Suchowola, Sokółka County, Podlaskie voivodeship). The research area is located in the Podlaskie voivodeship in the Brzozówka valley (left tributary of Biebrza River), in the Biebrza Basin. The described site is characterized by an oval form of anthropogenic origin, which indicates a permanent or temporary settlement in the prehistory. This object is one of many similar forms currently being discovered in Podlasie region.This form is build by two distinct trench rings separated by earth embankment and a central flat elevation with a diameter of about 60 m. A geophysical survey (geomagnetic and GPR) was carried out. They registered a series of anomalies, forming two rings which relate to the relief of the site. Archaeological excavation was made in the north-west direction. It was 25 m long and 2 m wide, crossing the embankment and both trenches.. In the course of archaeological excavations, ten objects were discovered with fragments of ceramics and a few flint tools. Preliminary results of archaeological research indicate that this structure was use by the communities of Urnfield culture in the Bronze Age.