This study investigates how linguistic devices are used to convey authorial stance in 36 Introduction sections and 36 Discussion sections of doctoral dissertations written in English by Thai students graduated in language education from different universities in the United States during the period 2008 to 2013. It also compares the use of authorial stance in the two sections. A concordance program called "AntConc" was used to detect authorial stance based on Hyland (2005)'s framework. The results of an independent sample t-test revealed that there were some sectional differences in the amounts, types, and functions of authorial stance. Pedagogical implications for EAP/ESP instruction and recommendations for further research are provided in light of empirical data.