Academic writing, particularly writing research articles, is an indispensable part of every major in higher education. Hyland (2004) argued that a valuable means of exploring academic writing, and comparing the rhetorical features and preferences of different discourse communities, is through the metadiscourse analysis of the text. The present study examines the differences in the use, type, and frequency of interactional metadiscourse markers in the introduction and conclusion sections of research papers across the two disciplines of Mechanical and Electrical Engineering. To this end, 42 research articles (21 Mechanical and 21 Electrical Engineering) written by English native speakers were randomly selected from two major international journals. The current study made use of Hyland's (2005) model for analyzing the interactional metadiscourse markers used in the selected corpus, consisting of 41484 words. To analyze the data, the frequency, patterns of use, and type of interactional metadiscourse markers were elicited both through a manual corpus analysis and concordance package. Furthermore, to examine whether there is any significant difference in the use of metadiscourse markers in the introduction and conclusion sections of these papers, a Chi-square analysis was run. The results of the quantitative analysis revealed that although there were some minor differences in the frequency and type of these metadiscourse markers, there was no statistically significant difference across the disciplines, which can be attributed to the close nature of these fields. The findings of this study may render some pedagogical implications for ESP courses and especially writing research papers.