Nowaday, Traditional Korean Gagok, both male and female singer sang five tone schale woo-jo (Shorten word for Woo-jo-pyungjo), whang(eb), Tae(f), Joong(ab), Yim(bb), Nam(c) and Kyemeon-jo(shorten word for Woo-jo-kyemeon-jo) whang, Joong and Yim. The seven out of eleven Woo-jo songs, are part of the Kyemeon-jo that are: Chosoo-daeyeop, Yisoo-daeyeop, Joong-geo, Pyeong-geo, Doo-geo, Samsoo-daeyeop and Soyong. In this paper, I compared melodic relationship in basic melody between Yisoo-daeyeop in Woo-jo and Yisoo-daeyeop in Kyemeon-jo. According to "Baekwoonam geumbo" and "Yanggum-shinbo", when Woo-jo song change into Woo-jo-kyemeon-jo, it only need to changed Goae(frets) of Komungo. The Jeong-dae-ueop's second song "Dok-kyeong'' is modulate into kyemeon-jo of Boraepyeong's second song "Ki myeong" which changed tae(D) into Hyeop(Gb) and Nam(A) into Moo(Bb). Likewise, In Traditional Korean music often found many case of modulation of the songs, for instance; the Yi-soo-dae-yeop (Woo-jo Yi-soo dae yeop) modulate to Kye-myeon-jo scale and become a Kye-meon-yi-soo dae yeop. Because, it uses same formation, beats and tempo and the lyric lines at same place. Not only that When it compared main structure of tones, it shows as same music. It only changed scale of the songs. These are the way of the modulation: 1. The Whang(eb)(basic tone of the Woo-jo) remain as Whang(eb)(basic tone of the Kye-meon) even it modulate into Kymeon. 2. The second tone of Woo-jo, Tae(f) change into the second tone of the Kye-meon, Joong(a b). the second tone of original five tone Kyemeon-jo was Hyeop(g b) but it changed into Joong. 3. The third tone of Woo-jo Joong changed into the third tone of the Kye-meon Yim(bb). Originally, the third tone of kyemeon Joong was same Joong of the Woo-jo but Tae took Joong's place. 4. When the fourth tone of Woo-jo Yim modulate into kyemeon, according to melody line of the previous or following melodies, it changes either Yim or Whang (octave high). When Joong of Woo-jo modulate into kyemeon Yim, the Yim become a Whang(Octave high), because the Moo, fifth tone of the kyemeon did not shows. and the Whang took the moo's place. 5. The fifth tone of the Woo-jo Nam(e b) rarely appeared, and the duration of the beat is also very short. Most of the time, the Nam uses as a lower pitch but it only appeared 3 -4 times. In this case, the Nam substituted with Whang because Moo did not appeared. 6. The following chart shows change of the tones 〈그림 참조〉 The Woo-jo Yisoo Dae yeop and the Kye meon Yi-soo dae yeop is the same song but only modulated into Kye meon scale. However, When the both song played, it sound totally different. why is it? because of the change of the expression of tone structures. The tone structure includes, change of the ornamentation, various melodies, vibratos(Yo-sung, Nong- eum), Pulling and pushing sound. Thus, the study of "expression of ornamentation" of this songs should follows, if that so the relationship of the between these two song will be define.