Modality is a complex grammatical and functional-semantic category which is reflected in various types of discourse. The relevance of studying epistemic modality, reflecting the author’s knowledge of the reported information and his/her attitude to it from the point of view of its reliability, is determined by the necessity to analyze the linguistic features of its expression in a scientific text. The aim of the paper is to study morphological, lexical-syntactical and lexical means of expressing modality and to identify their pragmatic functions in English-language texts concerned with engineering. The study of the linguistic component in a scientific text will help foreign researchers present their scientific works in accordance with the authentic features of English. This determines the theoretical significance of studying the author’s means of expressing epistemic modality as a method for reasoning their scientific propositions, interacting with the target reader and expressing academic responsibility. The study of theoretical works by foreign and Russian scientists has shown that epistemic modality of a scientific text implements mainly the properties of the author’s subjective approach. However, unlike other types of discourse, the modality of a scientific text identifies a certain degree of objectivity in the author’s approach since it is characterized by the assessment of the reported information in terms of its reliability/unreliability. The given study assumes that the category of modality of any text, including a scientific one, is difficult to analyze statistically. It is known that the expression of the English text modality is characterized by imperceptible “transitions” between different levels of its implementation. Therefore, the paper considers some linguistic means at the morphological, lexical-syntactical and lexical levels. They include the verbal category of the imperative, subjunctive and presumptive types of mood, infinitive constructions, modal verbs and modal words of various parts of speech with the seme “expectation/assumption”. The article underlines an additional pragmatic aspect of modality means in an English-language scientific text concerned with the need for soft persuasion of the professional community to accept the information presented.