在臺灣，人口結構老化已嚴重影響到中小學教師的需求量。各縣市為因應此一趨勢，要求學校有教師缺額不要聘滿、懸缺控管，大量進用代理、代課或兼任教師，導致剛取得合格教師資格者，若想進入中小學工作職場成為正式教師，通常都要先行代理、代課，對臺灣的師資人力產生不小的影響。本研究採深度訪談，混合滾雪球及分層立意抽樣之方式，以具有合格教師資格但背景多元的28位國中小代理教師為研究對象，進行二到三次的深度訪談，研究目的主要在探討代理教師在角色知覺、人際關係、學校生活、專業成長和生涯發展的困擾。結果發現，代理教師不想揭露其身分，是學校沉默的過客與局外人，且已經改變了原本穩定和長期的教師工作性質；而代理教師學校生活的擺盪、專業成長的倒置與生涯發展的停滯或中斷，也對代理教師產生困擾。

In Taiwan, the change of population structure has caused a decrease in the amount of formal teachers in middle and primary schools. For this trend, authorities in every county and municipal government require schools to reserve vacancies for formal teachers and hire substitute teachers or part-time teachers instead while making a reduction of the classes in the coming year. This trend has also caused an impact on Taiwanese teacher human resources and teacher education. The employments of substitute teachers will become an alternative process of teacher education. That is, most intern teachers must be substitute teachers before they have a chance to become formal ones. This research adopted the method of in-depth interviewing. It sought twenty-eight substitute teachers with teacher's licenses as study objects, mixing with snowball sampling and stratified case sampling. The purpose of this study is to understand the harassment of being a substitute teacher in his role-playing, interpersonal relations, daily life, professional development, and teacher career development.