Writing is one of the four skills in language learning and it should be paid more attention. In this regard, creating contexts which is value coherence in pragmatic level, and cohesion in semantic level is important. Knowledge about the discourse Markers (DMs), amongst other things, be used to improve writing skill. DMs are expression such as "now, well, so, which signal a sequential relationship between the current basic message and previous discourse. The present paper focuses on the instruction of the DMs and its effect on learners' writing ability. To do this, two groups as control and experimental were chosen from Shoukoh Iran English Institute in Tabriz, Iran. Both groups were asked to fill the gaps with the best option from among the DMs suggested. Then treatment sessions were conducted for experimental group while during that period, control group held back to receive such a treatment. Analyzing the misuse and inappropriateness of DMs occurring to their writing, pre-test, and investigating the relevant and suitable application of DMs appearing in their writing, post-test, and concludes with the suggestion that teaching text markers to learners should be paid more attention. And also the result reveals the effectiveness of teaching text markers to students in enhancing their awareness and sensitivity of discourse and consequently raising their writing levels.