在臺灣，客家語言居於三大漢語方言之一，臺灣每3.7人就有一人是客家人，2002年，於客家公共政策研討會上，客委會主委葉菊蘭表示：「根據學術界七年的調查結果，客家語言每年呈現百分之五的流失量，快則二十年後客家族群死亡，慢則五十年後客家族群會在臺灣絕跡。」其真正的原因何在？除了屈於生態環境的福佬化、隱形化之外，其成因是否如過去學者所言，是當年推行國語運動所產生的現象？還是受族群通婚的影響？這是本文所要探窮的動機。 本文以婚姻關係之下的客語使用，藉以分析客閩通婚為例的族群通婚，對家庭母語使用或調適取向，是以「父系」的語言為主？或是以「母系」的語言為主？抑或是受到優勢語言所影響？另外從筆者家族的客語能力來思考其衰退的原因，上一代的客家語言能力還相當不錯，那傳承之間是曾出現了問題？ 從現在的時代背景來看，從年輕一代客語聽說能力、客語語法能力等的認知，儘管「還我母語」運動熾勢的推行，客家母語教學的推動，但無可諱言的客家語言依然在消退中，如果要追究其真正原因，存在著相當的複雜性，影響程度的強弱有其歷史性、區域性、家庭教育等複雜因素，推行國語運動、族群通婚，家庭教育只是其中一環而已。由此觀之，基於客家外婚的對象以閩南為主；再則加上社會主流構通語言的國語使用，使得客家語言對內、對外的養成環境都遭遇被邊緣化的命運，確實是項值得省思的課題。

Hakka is one of the three main dialects in Taiwan, and one person out of 3.7 belongs to this ethnic group. However, Yeh, Jiu-lan, chairwoman of the Council for Hakka Affairs, once stated the “Language loss of Hakka reaches the degree of 5% every year, and some 20 to 50 years this dialect will become extinct”. The reasons that cause this happened may be due to the assimilation of the Hoklo dialect group, external marriage, and pedagogy in school. The factor of external marriage between Hakka and Hoklko is crucial. The dialect(s) spoken in such a family may be determined by either paternal or maternal side, or even the dominated lingual franca. A case study developed from the author herself reveals the situation of the deduction on the proficiency of Hakka speaking among generations. Despite of the classes of Hakka dialect teaching in school and the social movement of mother language speaking, the Hakka youngsters have poor proficiency and recognition on their mother tongue. The factors of language loss are sophisticated. Varying from historical, regional, and filial brought-up. The reasons cited in this article, such as language policy, external marriage, and family education are solely among many others. In sum, the marriage to a Hoklo spouse, and the dominated use of mainstream Mandarin, cause the peripheral position of Hakka dialect both in the family and society.