The present study investigates uses of evaluative that in English abstracts from 581 international journal articles and 346 master’s theses of Korean graduate students in applied linguistics. The aim of the study is to examine how the two differently proficient academic writers, i.e., expert journal writers and novice thesis writers, engage in rhetorical practices of evaluation in abstracts. The results indicate that the evaluative that structure is widely employed in both journal and thesis abstracts. The results also suggest that differences exist in the forms and functions of evaluative that in the abstracts of the two groups of writers. Specifically, the thesis writers differ from the journal writers in that they use somewhat unspecified information, express attitudinal stances without filtering, and present subjective judgments with an excessive force of persuasion. These findings have pedagogical implications for graduate students, especially those in applied linguistics. By demonstrating how expert writers in the field use evaluative that to make their claims and arguments persuasive, the findings can assist novice writers to develop competence in using evaluative that in disciplinary appropriate ways.