The purpose of this study was to analyze the structure and characteristic of teacher education system the State of Maryland in America while focusing on teacher license and training system. In America, teacher education system has changed since the teacher education reform in 1980's that intended professionalism of teaching. Professional Development Schools (PDS) have been one of the most important results from this reform. PDS are public schools in partnership with universities which aim to improve teacher education and to enhance the expertise of teacher candidates or school teachers. The State of Maryland is one of the states which had involved PDS most positively, because the State Department of Education has played a key role. Recently the State Department of Education has implemented the new policy in teacher training system, so it is important how teacher license and training system are conducted in PDS. The findings from this study are as follows: (1) When teachers renew their license, many teachers earned the required credit through professional development activities in school district and not through university courses; (2) Many teachers have put emphasis on school-based activities in professional development activities because they seek practical knowledge and skills; (3) Teacher education system closely premises school-university partnership, therefore universities need to be continuously involved with teacher training system.