One of the most critical differentiator of skills in chest x-rays diagno-sis is an effective information acquisition strategy coupled with thorough medical knowledge. However, well-experienced doctors frequently find it difficult to explicitly explain their skills because such skills are implicit and automated. To uncover characteristics of skills in chest x-rays diagnosis, we monitored eye movements as well as their debriefing utilizing the eye movement data, seventeen medical doctors including experts, intermediates, and residents during diagnosing twenty chest x-rays. Based on debriefing and eye movement data, we discuss possible application of eye movement data for effective education system. Keywords: Gaze Pattern, Expertise Analysis, Clinical Reasoning Process, De-briefing, Chest X-Rays.