屏東縣客家事務處為了挽救客語式微的危機，於幼托園所積極推行客語沉浸教學計劃。本研究主要的目的在瞭解客語沉浸教學幼兒之客語使用情形，主要研究問題包括：（1）針對不同交談對象，客語沉浸幼兒之客語及中文使用比例狀況為何？（2）針對不同學習活動型態，客語沉浸幼兒之客語及中文使用比例狀況為何？研究場域主要是在一位績優客語沉浸教師的班級中進行，研究人員先密集觀察班級一個月後，再選出四位不同語言背景及性別的幼兒做更深入的觀察及分析。研究結果顯示：（1）幼兒在與教師互動時，客語使用的比例高於中文的使用比例；而幼兒與幼兒互動時，中文使用比例高於客語使用比例，且比例相差懸殊；（2）在不同學習活動型態中，團體活動中的客語使用比例高於中文使用比例；小組活動時的中文使用比例高於客語使用比例。研究者從語言位階、語言使用型態、語言能力及幼兒年齡等因素探討可能造成此狀況的原因。文末，提出客語沉浸教學相關教學及政策上之建議。

To preserve at-risk Hakka language, Pingtung Hakka Affairs Department implemented the Hakka language immersion programs in early childhood settings. The purposes of this study were to understand the situation of children's language use in Hakka immersion program. The main research questions included: (1) What are the percentages of Hakka and Chinese language uses when children talked to teachers and peers? (2) What are the percentages of Hakka and Chinese language uses when children in different types of activities? Researcher chose one outstanding Hakka immersion teachers' classrooms as the main research field. Research first observed the classroom intensively for one month, and then chose four children with different language backgrounds and genders to do further observation and analysis. Research results were: (1) when interacting with teachers, the percentage of children's Hakka language use is higher than that of Chinese use. However, when interacting with peers, the percentage of children's Chinese use is higher than that of Hakka language use. The gap between different language uses is large; (2) when participating in group activities, the percentage of children's Hakka language use is higher than that of Chinese use. When participating in small-group activities, children's use of Chinese is higher than that of Hakka language use. Researcher discusses language status, language types, language ability, and children's age as possible influential factors. In the final part, researcher provides some suggestions for Hakka immersion program implementation and related policy.