This study attempts to look into the issues that secondary students have faced when using cohesive devices. To achieve this purpose, the research has adopted descriptive method by using a questionnaire, the sample consist of 150students and 150 teachers in secondary school of Diyala Governorate during the academic year 2021-2022. The researcher has analyzed the data by using the statistical program (SPSS). The researcher designed a questionnaire made of 25 items for students and 28 items and personal information for teachers.The outcomes of the study confirmed that students at secondary school have difficulties in using grammatical and lexical cohesive devices in writing. Additionally, the study advised English teachers to support their students' usage of various cohesive devices in their writing.