The objective of this study is to examine the use of word spacing and punctuation marks targeting the elementary school Korean language textbooks in the Japanese colonial era and the U.S. military government period. The word spacing and punctuation marks in textbooks allow the efficient learning by raising the readability. Even in the enlightenment period when the norm of Korean language was not clearly established, there were relevant discussions. After the ｢Draft for Hangeul Unified Spelling System｣ was distributed by the Korean Language Society during the Japanese colonial era, it started to be more actively applied. In the elementary school Korean language textbooks written in Hangeul, the use of word spacing and punctuation marks is essential. Thus, changing from the use of punctuation marks for vertical writing of Korean-Chinese mixed style to the method of using the word spacing and punctuation marks, they were more fully shown in horizontal writing. The change in writing style became a chance to subdivide the punctuation into word spacing and punctuation marks, which is shown in Korean language textbooks in the Japanese colonial era and the U.S. military government period.