The article discusses Balto-Slavic contacts in Upper Neman, based on the generalized results of archaeological studies. The statement, that the forming of a wide contact line but not a sharp border region has become the result of the mentioned contacts suggested by researches, is pointed out. The ethnic context of the contact line is mostly Eastern Slavic and Western Baltic (the Dregoviches and Yatvingians) but not Eastern Slavic and Eastern Baltic as it has been assumed before.