This aim is to clarify thinking process of nursing students’ clinical judgment, i.e., how nursing students act and think and what influences this thinking process of identifying approaches necessary for the children under their care in pediatric nursing practicum. By the analysis of M-GTA, students concurrently performed “A: Analytically contemplating the state of this child’s body” and “B: Contextually contemplating this child’s individuality”. As a result, they acquired “C: Understandingof this child as a familiar existence.” This allows students to enable them to “D: Identify the necessary approach using judgment criteria for this child.” Furthermore, as situations that promote thinking by relating to all processes of thinking, students experienced “E: Attempts to solve problems through various measures” and “F: Encouragement of thinking through reflection.” Meanwhile, “G: Stagnation of thinking because of concerning matters” inhibited the progress of thinking. We found a need for education after grasping the process of student thought.