An Error Analysis of EFL Undergraduate Students' Writing Composition in Universitas Tanjungpura. Objective: This study has thoroughly investigated morpho-syntactic errors in the compositions of English Language Education undergraduates at Universitas Tanjungpura. Methods: Employing a descriptive methodology and drawing from Ellis (1994), the research analyzed 97 self-descriptive compositions. Findings: The findings reveal a significant prevalence of morphosyntactic errors, totaling 793 syntactical and 333 morphological errors across an average of 18 sentences per composition. Syntax errors involve sentence patterns and subject-verb agreement, while morphological errors revolve around inflection and conversion challenges. Categorized into omissions, additions, misinformations, and misorderings using a surface strategy taxonomy, the errors provide insights into students' linguistic competence. Conclusion: The study advocates for targeted instructional interventions, integrated curriculum development, cross-linguistic awareness programs, and learner-centered approaches.