This research aims to gain a deep understanding of the learning difficulties of students in the subject matter of mathematical sentences and calculations in Grade IV of SD Negeri 3 Kutasari (Public Elementary School 3 Kutasari). The research uses a mixed methods approach. The subjects of the study are five Grade IV students who were selected based on their below-average learning outcomes. The data obtained consists of descriptive test questions, interviews, and observations of students, which are analyzed qualitatively. The quantitative analysis reveals the following errors made by the students: errors in reading and understanding the questions (23.47%), errors in transformations (20.40%), errors in calculations (21.43%), errors in process skills (12.24%), and errors in conclusions (22.44%). Additionally, there are several factors contributing to the learning difficulties of students. Internal factors originating from within the students themselves include low interest in learning, the students' knowledge and abilities. External factors caused by external influences include social factors (family environment, play environment, and school environment) and pedagogical factors (teachers lacking creativity in using media and teaching methods). To address the learning difficulties of students, efforts are made through improvements or remedial actions based on the evaluation of learning outcomes and practice exercises. Teachers are advised to use attractive teaching models and media to create enthusiasm for learning among students. They should also establish good communication with parents to monitor students' learning while they are at home.