In 1624 a detachment of the Dutch East Indies Company landed in Taiwan and began 38 years of colonization. Ten years after their invasion, some of their group transcribed the local language phonetically by means of Latin alphabets and recruited the native people to learn the system, teaching them their indigenous language in script as well as the Dutch Protestant doctrines in translation. The dominant local language selected for translation and proselytization was Sirayan, an Austronesian language. Such texts written in Dutch alphabets were branded as ＂red-haired language.＂ Initially, the ＂red-haired＂ depicts the Dutch and things related to them. Eventually the term becomes a common name for all matters from the Western world. In fact, this descriptive term ＂red-haired＂ is quite popular in Southern China. Dialects such as Cantonese, Taiwanese and Mandarin still preserve the label, to address Western people in general as ＂red-haired barbarians.＂ By means of historical data and documents, this paper probes into the red-haired remnants in Taiwan and reinvestigates the concept of ＂red-haired＂ anew. This will involve social mores, educational strategies and evangelization intent of the Dutch Protestant Church as well as the Dutch East Indies Company policies. The focus is on the Dutch handling of the Sirayan language, shaping up an oral language into a written one. Unlike the ＂Rangaku＂ (study of the Dutch/Western culture) phenomenon in Japan, the codification of the Sirayan written language has not developed to become a means for the Taiwan aborigines to absolve Western culture. Nevertheless, this Sirayan ＂red-haired language＂ accords us with new light to understand the neglected role of the red-haired people during the cultural interaction between Taiwan and Holland in the 17th century.