This study aimed to identify the types of cohesive devices used by the teacher during the teaching-learning process. The data were analyzed using Halliday and Hasan's theory (1976) taken from the transcript of the English teaching video recorded in the private high school in Lampung. The method applied in this research was a descriptive qualitative method that provides an overview and interpretation of objects in the actual situation. The results of this study show that the most frequent cohesions that appeared in the conversation are reference 30,77%, ellipsis 33,33%, conjunction 23,08 %. Meanwhile, the occurrences of substitution were 5,13%, and lexical cohesion which included reiteration 7,69%, and collocation (0%) in lexical cohesion. In the teaching dialogues, simple sentence is preferred such as giving explanation, instruction, or complaining about something. In addition, omitting words is mostly used than substituting, also more ellipsis than substitution. Discourse cohesion devices used in the teacher conversations include all cohesion except the collocation as Halliday and Hasan stated, here the researcher found that the cohesive devices that were mostly used by the teacher were the ellipsis and references.