Grammar has an important role in all skills in the English language because grammar makes the four skills are meaningful, but many English language education students produced errors in their writing regarding grammatical aspects. The main purpose of this research was to analyze the types, the frequency, and the source of the grammatical errors in writing an abstract of the skirpsi made by English language education students at the University of Islam Malang. This research was conducted in a descriptive qualitative method. The sample of this research was 30 writing abstracts made by English language education students 2017-2018 academic year that were collected by simple random sampling. The researcher collected the data by using observation and documentation techniques. The process of data analysis was organizing and preparing the data for analysis, reading all of the data, beginning detailed analysis with a coding process, using the coding process, making interpreting and meaning the data, and drawing a conclusion. The errors were classified into linguistic category theory as proposed by Dulay et al, (1982). The findings showed students made some grammatical errors of omission of article 116 items (67.05%), substitution singular to plural 35 items (20.23%), disagreement of subject and tenses16 items (9.24%), substitution singular to plural 4 items (2.31%), omission of to be 1 item (0.67%), and omission of main verb 1 item (0.57%). The sources of the grammatical errors were interlingual transfer, limited knowledge of English grammar, and carelessness. Based on the finding of this study, the researcher concluded that although students have learned English grammar for about four semesters in the University they still have possibility to make an error in their writing abstracts of skirpsi. Therefore, the researcher suggested to the lecturers of English language education to focus on teaching grammar and writing and give more grammatical exercises both spoken and written to the students. The students of English language education should pay more attention to using English grammar, do writing exercises and make peer feedback before publishing their writings. The researcher hopes this finding of the study can inspire the next researchers to conduct other researches related to the grammatical errors analysis to enrich the exiting studies. Key Words: Grammatical Errors, Abstract Writing, Skripsi