Global health education programs have grown in number and rigor with the development of learning objectives, competency frameworks, and assessment tools. This study aimed to assess whether prompted reflective writing could demonstrate medical student learning of physician competencies during global clinical rotations. From 2014 to 2018, 135 medical students who participated in global health clinical rotations responded to four reflective writing prompts. We conducted qualitative content analysis of 487 individual responses using grounded theory and an iterative process to identify themes associated with the eight American Association of Medical College physician competency domains. In response to prompted reflective writing assignments, students demonstrated learning related to all eight competencies. They reflected on systems-based practice while also sharing their growth in knowledge and skills related to personal and professional development, knowledge for practice, interprofessional collaboration, and patient care. In demonstrating practice-based learning and improvement, students additionally reflected on how the experiences during their global clinical rotations might influence their future careers as physicians. Our findings suggest that prompted reflective writing during global clinical rotations allows medical students to demonstrate learning in the competency domains expected of all physician trainees and to reflect on the application of this learning to current and future patient care. In reading students’ writings, we found that prompted reflective writing during global clinical rotations offers an opportunity for students to illustrate the knowledge and skills they have acquired as physicians in training.