This study has measured the scores on the memory tests for Korean Japanese learners with hearing impairment on such Japanese vocabulary hardly learnt in written language and analyzed these results. It is aimed to recognize the need of a research on proper learning and teaching methods of the Japanese vocabulary for hearing impaired learners, and to seek the potential availability of the JSL as an effective method to teach them Japanese vocabulary. First, as a result of the memory test for such written language on rarely learnt verbs, there has appeared no difference in the test scores between short-term and long-terms memories for the Japanese written language. Second, as a result of what is found in the course of the change in the target group`s desire to learn the JSL in the survey conducted twice before and after the memory tests for the target group participated in this study, the ratio of their learning desire showed a bit of a rise after the tests, and in a free descriptive way of the survey has appeared that Korean Japanese learners with hearing impairment are more likely to have high desire for and interest in the JSL. Third, it has shown that Japanese learner in Korean School for the Deaf think that learning tools such as visual image data would be useful for such learners who were the subjects in this research, and visualized learning materials including the subtitles and the JSL gestures expressed which were actually used in this research would be of help to them in learning Japanese vocabulary. In other words, it has been analyzed that the subjects consider the sign language learning experience through Japanese hearing impaired people having the same hearing disorders as they do to be a more effective and proper method of learning.