Inner speech is accessible through its manifestations in intrapersonal and interpersonal communication. The deep structure of the inner speech has to be reconstructed through these manifestations. The manifestations of the inner speech can be found in slips of the tongue (cf. S. Freud), in the metaphor signifying the condensation,of the meaning in the symptom, and in the metonymy signifying the displacement of the meaning in the desire (J. Lacan). The experiments in thinking brought manifestations of inner speech in additional reports of subjects on own process of thought (cf. K. Buhler). The experiments in the thinking aloud brought manifestations of the inner speech connected with the problem solving process, such as the functioning of semantic complexes (cf. A. N. Sokolov), and the functioning of inner symbolic structures (cf. A. Newell, H. A. Simon). The experiments in communication using the methods of speech and non - speech hindrances showed the recoding role of the inner speech (cf. N. I. Zhinkin). The author's method of regulated (controlled) dialogue allows to find the manifestations of the inner speech through added and omitted expressions in the recall of the uttered replicas. Also the additional report of subjects in the form of indirect speech in the past sense was used. The coincidences and differences of categorizing expressions like "I proposed that...", "he objected that..." manifest the inner speech processes, too. For the analysis of the indirect discourse as a whole the ideas of G. Frege can be used. According to him the expressions like he said that..." alter what the words in the following subordinate clause refer to. While the reference of the main clause with he said that..." is the truth - value, the indirect reference of the subordinate clause is its ordinary sense, the customary thought. For understanding this thought is not necessary to hold it true. The speaker connects the main clause with the subordinate clauses and thoughts either expressed or tacit ones. Similarly, the recipient connects the main clause of the speaker not only with the speaker's expressed dependent clauses and thoughts, but also the expected or imagined dependent thoughts both of the. speaker and of one's own. In this getting over the content of the main clause the manifestations of the inner speech both at the speaker and at the recipient can be found.