Abstract is one of the essential parts of thesis, is used as the first impression for the reader and it also attracts readers’ attention whether they need to read the full research or not. The abstract should be written as a cohesive text, not only a set of unrelated sentences. This research is aimed to analyze the cohesion in abstract of theses written by undergraduate students of English Language Education Study Program (ELESP) of Lambung Mangkurat University. Specifically, this research analyzes the types and the dominant cohesive device used by ELESP students in writing their abstracts. Qualitative research was used in this research in analyzing the data. The data of the research were 36 abstracts written by ELESP students batch 2014. The researcher used himself, analysis guidance, and documentation as the instrument of the research.The result showed that the cohesive devices that the ELESP students used in writing their abstract were reference, ellipsis, conjunction, reiteration and collocation. However, the researcher did not find any substitution in ELESP students’ abstracts. Reference was dominantly used followed by reiteration, conjunction, collocation. Meanwhile, ellipsis was rarely used by the students in writing their abstract. Although not all cohesive devices found in every students abstract, the cohesiveness of the abstracts were still maintained with the appearance of the other cohesive devices.