The objectives of the research were to find out and analyze not only grammatical error but also errors in arranging formats of application letters made by sixth semester students of management program in academic year 2015/2016. The research was conducted in May 2016. The method of this study used descriptive research. The subjects of this research were 36 sixth semester students of management program at Muhammadiyah University of Purwokerto. In collecting the data, the researcher asked the students to write an application letter based on the job vacancy given. The grammatical errors were classified based on surface strategy taxonomy, they were mis-formation (44.19%), omission (26.16%), mis-ordering (20.35%), and addition (9.30%), while errors in format application letter were based on Geffner (1995). The grammatical errors were first classified into nine major categories and then they are divided by sub-categories. After observing, it was found that the largest number of errors were verbs (30.23%), after that adjectives (21.51%), followed by preposition (16.86%), articles (9.88%), tenses (9.88%), pronoun (5.29%), plural (2.91%), adverb (2.33%), and the least is noun phrase (1.16%). Inter-lingual and intra-lingual transfers were considered as the cause of these errors. Furthermore, the errors in arranging layouts of application letter based on UK concept were classified into 6 categories, and the highest number of errors was found in enclosures (24.64%), followed by sender addresses (20.29%) , after that complimentary close (16.67%), then salutation (15.22%), date (14.49%), and the last was style (8.70%).