Purpose: This study was conducted to explore the perceptions and characteristics of in-service and prospective teachers regarding the educational ‘field’ and to identify the differences. Methods: Twenty-three current biology teachers from across the country and 21 prospective biology teachers from universities in the southern region participated in the study. The questionnaire-collected data was analyzed qualitatively, and this presented results using simple descriptive statistics. Results: While in-service teachers emphasized ‘reality’ by presenting the concept of ‘field’ acquired through experiences in the educational field, prospective teachers conceptualized an ‘ideal’ of the field that was somewhat abstract and distant from reality. The in-service teacher responded that the perception of the field that he had as a pre-service teacher changed very realistically as he experienced the actual field. Through their field experience, the teachers suggested a curriculum-related curriculum, the acquisition of experimental inquiry class operation skills, the development of administrative skills, and the expansion of school field training as measures to strengthen field experience in the teacher training curriculum. Conclusion: Through these results, this study suggested that the definition of ‘field’ should be specified first before evaluating teacher training courses and teacher training institutions, and that the opinions of current teachers should be sufficiently listened to and reflected when establishing a teacher training curriculum.