The objective of this research is to find the errors that are generally made by the students? writings in analytical exposition text. This research was carried out on 16th May 2007 until 4th June at SMA Negeri 56 West Jakarta. The writer analyzed 30 students at the second grade students by making analytical exposition text. Qualitative analysis is the technique of data analysis in this research. This analysis starts from meeting the schoolmaster, getting the information from the English teacher, preparing the tasks writing material, arranging the time to do the research, coming to school then asks the students to make an analytical exposition text, collecting the students? writing, identifying the errors and the mistakes, giving the first writing, collecting the second writing, identifying the second writing, explaining types of errors, making reconstruction, classifying the errors, identifying the most difficult errors, and giving the therapy to the students. Based on the error calculation it is found: the most errors that are generally made by the students are Addition (22.46 %), Word Choice (17.92 %), Omission (13.76 %), Singular-Plural (12.59 %), Verb Tense (10.64 %), Meaning Not Clear (7.01 %), Spelling (5.06 %), Incomplete Sentence (3.37 %), Word Form (3.11 %), Misordering (0.90 %), Capitalization (0.77 %), Punctuation (0.64 %), Run On Sentence (0.64 %), Double Marking (0.51 %) and the least errors has made by the students is Article (0.51 %). From the simple statistical calculation above, it shows that, generally, the teaching of English grammatical aspects in writing has not been successful, especially, in the aspects of Addition, Word Choice, Omission, and Singular-Plural.