The paper publishes the results of a study of complex B of Pezmogty 3 site. The author has studied traces and remains of a depressed small dwelling with an excavation area of 81 m. The spatial distribution of artefacts, faunal remains and their association with deposits of different genesis have been analysed. It is defined that the studied structure was rounded in the plan, 3,0-3,5 m in diameter, 7-9,5 m in area, and, probably, a cone-shaped roof. The assemblage contains stone objects, fragments of ceramic ware and indeterminable items, fragments of calcified bones. The morphology of the flint arrowheads; the signs of secondary bifacial thinning technology; the ceramic pots, made of clay with an admixture of silt and decorated with a comb-pit ornament, allow us to attribute these materials to the Lyalovo culture in the European North-East and date them to the first half of the V millennium B.C. Until now, the most informative data for the study of this culture in north-eastern Europe were the remains of medium and large dwellings with an area of 26 to 100 m, so the published materials expand our understanding of the way of life and house-building traditions of the Middle Neolithic people of this region.