Character education at the elementary school level should be integrated into learning so that character values are internalized through students’ experiences and interactions. Cooperative learning supports this process by encouraging collaboration and group interaction. This study aimed to describe the implementation of cooperative learning in strengthening the character of fourth-grade students at SD Negeri 1 Jatinom, focusing on mutual assistance, cooperation, responsibility, tolerance, and mutual respect. A qualitative descriptive approach was employed, with data collected through classroom observations, interviews with the fourth-grade homeroom teacher, and documentation of student activities. Data were analyzed through data reduction, data presentation, and conclusion drawing, while validity was ensured through triangulation. The findings indicate that cooperative learning is implemented through group activities that encourage students to discuss, collaborate, help one another, and complete tasks together, fostering behaviors that reflect mutual assistance, cooperation, responsibility, tolerance, and mutual respect. Teachers act as facilitators and mentors by guiding interactions and reinforcing positive behaviors, while the school environment and collaborative habit-forming programs further support character development. Although consistent application of character values across different activities still requires continuous guiandce, cooperative learning proves to be an effective strategy for strengthening students’ character through meaningful interaction and collaborative experiences.