The textbook reveals the basics of the theory and practice of the scientific style of the Russian language in the field of humanities, natural and exact sciences. The book discusses the substantive and structural features of the scientific text, some issues of grammar, terminology and phraseology of the scientific style, as well as the main problems of teaching languages ​ ​ to foreigners in non-philological specialties. Original author's developments are offered for teaching reading, listening to lectures, and mastering the skills of oral and written professional speech.