WAGIYENI NUR AGIYANTI. NIM: 0701065209. An Error Analysis on the Eleventh Grade Students Job Application Letter at SMK Islam Al Hikmah South Jakarta in 2011/2012 Academic Year. A Paper, Jakarta, The Study Program of English Education, The School of Teacher Training and Education, University of Muhammadiyah Prof. DR. HAMKA, 2012. The objective of the study is to find out the errors of students? job application letter writing. This study was carried out at the eleventh grade students in the second term of SMK Islam Al Hikmah South Jakarta in 2011/2012 academic year. The method of the study is descriptive analytical method which is to describe and analyze the grammatical errors made by students on their composition. In this study, the writer uses a job application letter writing to collect the data as the instrument of this research. The writer took the eleventh grade of accounting 2, which consists of 32 students as population. In doing data analysis, the writer only takes 20 students writing sheets as the sample. Based on the result of the data analysis, the writer found that the most common errors the eleventh grade students of accounting 2 had done in omit a word with 30.92%, followed by errors of add a word with 12.21 %, word choice with 10.31 %, spelling with 9.16 %, word form with 8.02 %. In accordance to the above typical errors, the writer found out that the most sources which cause students writing the errors are interlingual transfer with 37.55%, intralingual transfer with 44.08%, contexts of learning with 2.45%, and communication strategies with 15.92%