In the article the approaches to the problem of political discourse speech genres differentiation are discussed based on the comparative analysis of the German and Russian public parliamentary speech authentic samples. The special status of the public speech phenomenon in parliamentary communication and its conditionality by parliamentary regulations are discussed. The communicative roles of plenary sessions' participants in Germany and Russia are described. In both parliaments, public parliamentary speech is exercised in a dialogue form, managed and controlled by the president of the Bundestag / presiding plenary session. The existence of common political goals of German and Russian public parliamentary communication proves the expediency of its comprehensive comparative study, taking into account extralinguistic and linguistic characteristics of public parliamentary speeches. The statements, representing the German and Russian public parliamentary speech, form a set of institutional genres, the emergence and functioning of which are predetermined by the parliamentary regulations. In both parliaments, they include a report, a statement, a question, and a reply, presented in several intragenre varieties, with specific national variants. Each of these genres is characterized by the use of specific methods of language expression, emotional utterances, rhetorical and polemical techniques It is indisputable that the language plays an important role in parliamentary communication. As J. Searle considers, like other public institutes, the language can also be considered as an institutein a narrow sense of the word. It is such an institute which, unlike other institutes, cannot be abolished by a resolution [6]. Without the language which is a cornerstone of "organizational rules of a discourse" [7], not only verbal communication in general, but establishment of modern public institutes is inconceivable. According to J. Charteris-Black, for designation of the language of public parliamentary communication we can accept the term "parliament language" [8].