The aim of this paper is to describe how the rethorical relations cause and result are expressed in formal elocutions (lectures). By the Rethorical Structure Theory aplication, functional theory developed by Mann e Thompson (1987) which describes the established relations between the parts from a text, itís intended to verify the relations cause and result relevance in a construction of a discourse which are proposed to explain and teach, according to its kind of mark in a particular lecture context. The relations were indetified in the corpus, and after they were classified s the sort of mark. Then, it was observed how de relations were applied to the lectures, who were the informers, got their comunicatives purpose. The research corpus is formed by 10 formal elocutions (lectures) which belong to Funcpar (Functional Research Group on North/ North-East of Paran·) database. The subjects of the research are university lecturers who were born in Maring· (PR) or have lived in it for at least 10 years. The data were recorded during graduation classes and were transcribed according to a pattern based on NURC project (PRETI, 1993, p. 11-12) with a few adaptations. The segmentation of the units of the corpus followed Chafeís (1987) concept of intonation units. Results indicate the analysis of the cause and result relations in the teachersí speech not only contributed to their purpose of teaching...