Abstract
This study identified and analyzed epistemological obstacles experienced by prospective elementary school teachers in solving mathematical literacy tasks on plane geometry material. This study employed a case study method, involving 24 students from a university, which was located in Cimahi City, West Java. The diagnostic test served as the research instrument and the data were analyzed using a thematic analysis approach to uncover various epistemological obstacles encountered by undergraduate students, including misconceptions regarding the properties of plane figures and difficulties in applying geometric concepts to mathematical literacy tasks. Epistemological obstacles arise due to the students' inability to connect abstract concepts with practical contexts, as well as their limited understanding of basic geometric concepts. These obstacles primarily stem from misconceptions about fundamental concepts of plane figures, difficulties in applying geometric concepts in contextual situations, and procedural learning approaches that lack conceptual depth. This research contributes to developing geometry learning strategies at the elementary school level, which can ultimately improve the overall quality of mathematics education.