This study aims to analyze problems of cohesion in the college writing and to provide teaching materials for the college writing education. In this study, I categorized problems of cohesion found in texts KAIST students wrote into repetition, pro-form, ellipsis, conjunctive, and functional sentence perspective according to Beaugrande & Dressler (1981). Cohesion is the first element of textuality Beaugrande & Dressler (1981) were discussed, it tells connection between language constituents construct text. It is a main condition paragraph and text must get ready. But many college writing textbooks don't give sufficiently explanation and examples about cohesion, and cohesion education is left to the discretion of the teacher. Therefore the result of this research which analyzed problems of cohesion showed in writing of college students is going to be useful as real language data for cohesion education.