This study is a qualitative case study with four teachers who have experienced the probational teacher system of the Sejong City Office of Education as participants. As a result of the study, they wanted to quickly become teachers, so they tried to find temporary positions, and in the process, they applied for a probational teacher through the recommendation of their seniors or the education office. After being the probational teachers, they experienced minimum guidance , helpful classes , and ‘limited discipline during supporting school classes and various classroom management , various school atmosphere and drifting life during attending various schools. In short, such experiences can be called fast, diverse, but lonely experience. The meaning of probationary experience was tasting, accumulating, and standing alone . In other words, the experience was a process of socialization that allowed probational teachers to taste the sweetness and bitterness of teaching life, accumulate knowledge and ability, and stand alone based on it. Based on the results, it was suggested that the current system, which focuses on supporting school classes rather than on the growth of probational teachers, should be improved, that administrative and institutional support should be supplemented, and that the designation of guidance teacher for probational teachers needs to be considered. The number of probational teachers hired every year is increasing. So, if some of these suggestions are accepted, it is expected that the original purpose of the probational teacher system, called ’improving field application‘ of new teachers, will be well fulfilled.