<![CDATA[This research aims to identify types of learning difficulties, analyze contributing factors, and map error patterns of students in learning triangle material through a literature review approach. The research method employed was library research with content analysis techniques on eight relevant scientific publications published between 2021-2026. Data were collected through literature searches in academic databases and analyzed qualitatively using the learning obstacle theoretical framework. The findings reveal that students' difficulties manifest in five dimensions: difficulty in translating problems, understanding fundamental concepts, applying mathematical principles, performing spatial visualization, and completing systematic procedures. Contributing factors include ontogenic obstacles related to cognitive development limitations, epistemological obstacles stemming from misconceptions and weak prerequisite mastery, and didactical obstacles associated with conventional teaching methods. Students' error patterns were identified at each problem-solving stage, from understanding, planning, executing, to verifying solutions. This study concludes that learning difficulties in triangle material constitute a multidimensional phenomenon requiring instructional interventions based on Van Hiele theory with gradual scaffolding, utilization of visual-manipulative media, and continuous diagnostic assessment to enhance geometry learning quality comprehensively.]]>
