This research was conducted at SMK Bina Bangsa on the Second Grade students of Accountant Department aiming of finding out the most typical errors and the causes of error which are made by the students in writing. Based on the aim of the research, the writer uses a descriptive method. In collecting the data the writer administers a kind of writing test to students. Then, the writer analyzes the writing errors done by the students. The result of the research revealed that common errors on the students' writing ability were the error of verb tense (13.91%), errors in incomplete sentence (11.92%), errors in add a word (11.26%), errors in omit a word (9.93%), errors in word form (8.61%), errors in spelling (7.95%), errors in meaning not clear (7.95%), errors in singular-plural (5.3%), errors in word choice (5.3%), errors in punctuation (4.64%), errors in capitalization (3.97%), errors in article (1.99%), errors in word order (0.66%) and errors in run - on sentence (0%). The result of the research revealed that common errors on the sources of error were in interlingual (30.46%), overgeneralization (13.91%), ignorance of rule restrictions (48.34%), in-complete application of rule (0%), and false concept hypothesized (7.28%). It indicates that most of students need more treatment and remedial teaching from the teacher toward their errors in English writings and the second grade students of SMK Bina Bangsa Ciledug still need more practice in order to develop their writings.