The aim of the study is to investigate the errors in writing of non- English major students at Thu Dau Mot University. This study focused on paragraphs because the researcher has found that diverse errors in students’ paragraphs and wants to improve their writing skill. Seventy-four English paragraphs were written by 74 non-English major students coming from different academic majors at Thu Dau Mot University. All of the errors in the paragraphs were identified, synthesized and classified into various categorizations. The findings of the study show that the most frequently committed errors were tense, spellings, singular/plural form, prepositions, word order, fragment. On the basis of these results, many recommendations and pedagogical implications were suggested to help EFL lecturers with some teaching strategies that will reduce problems regarding writing English paragraphs among English learners.