This study aims to build a new list of basic vocabulary of the national English curriculum, thereby promoting the development of textbooks with authenticity. In order to achieve the purpose, it first analyzed the guideline for vocabulary use that the present national curriculum provides and then identified its problems and issues. For a new list of basic vocabulary, instead of compiling a list of individual words, a total of 2790 word families with high frequency were selected based on the corpora of General Service List, British National Corpus, American National Corpus, Oxford University Press 3000, Longman Written 3000 & Spoken 3000, and Essential words of Cambridge. The 1000 word families with the first high frequency were selected as vocabulary appropriate for elementary school students. For homographs, they were regarded as different. The new list excluded proper noun, month, day, cardinal and ordinal number, unit, and the Romanized Korean. This study provided policy suggestions for successful development of English textbooks with authenticity. It is expected to be a preliminary study for the new national English curriculum which is supposed to be amended in 2011.