In the practice of teaching in the field, many EFL students face difficulties in understanding and applying L2 grammatical rules. For this reason, this study aims to analyze the spoken grammatical errors made by the first year students of SMAN 3 Banda Aceh. This study focused on the analysis of the grammatical error types in terms of communicative effect taxonomy, namely global error and local error. The research method used in this study was descriptive quantitative research. To collect the data, the researcher used oral test. The result shows that students produced missing, wrong, or misplaced sentence connectors (96.29 %) and wrong order of major constituents (3.70 %) of global error, and verb inflection (60.29 %), auxiliary (10.77 %), prepositon (8.08 %), article and noun inflection (6.39 %), misordering (5.72 %), and pronoun (2.35 %) of local error. The most dominant error was local error (91.66 %). It is highly recommended that EFL teachers should be more aware of most frequent errors made by the students and use more effective techniques and strategies in teaching grammar. To conclude, the grammatical errors of students' spoken English were still mainly influenced by interlingual and intralingual transfer.