2021-Present, Professor and Head of the Department of Pathology, Konkuk University College of Medicine

2005-2010, Associate Professor, onkuk University College of Medicine

2014-2015, Director, Education and Training Department, Konkuk University Medical Center

2012-2013, Deputy Director, Education and Training Department, Konkuk University Medical Center

2005-Present, Head professor, Pathology, Konkuk University School of Medicine

2003-2004, Research Fellow, Division of Pathology, National Surgical Adjuvant Breast and Bowel Project Foundation(NSABP), Pittsburgh, PA, USA

2000-2002, Chief, full-time instructor, assistant professor, Department of Pathology, Nowon Eulji Medical Center, Eulji University

1997-1999, Researcher, Department of Tumor Research, Korea National Institute of Health

1993-1996, Resident, Department of Pathology, Hanyang University Hospital