This research was conducted to find the effects of the addition of kugija to the quality and conservativeness of Nabak kimchi. Kugija extract was prepared by boiling kugija fruits, at different ratios (1, 3, 5 and 7%; w/v) in water for 30 minutes. The changes in the sensory and microbiological properties of the Nabak kimchi were measured for 25 days, following the preparation at a uniform temperature of 10$^{circ}C$, and compared to a control (distilled water without kugija). For the properties of acceptability, the Nabak kimchi treated with 3% kugija was evaluated as being best during the whole fermentation. The number of total cell counts and number of lactic acid microorganisms gradually increased to a maximum, and then decreased. It was the maximum for controlling and 1 % treatment on day 2, forand 3, 5 and 7% treatment on day 7. (Eds note: the highlighted sentence needs c1arificationulcorner)This experimental study revealed the effect of kugija extract in enhancing the eating qualities on Nabak kimchi and retarding the fermentation over the initial seven days. The optimum levels of kugija extract on Nabak kimchi obtained through experiments was between 1 and 3% of the water content. Although 3% gave a better color, the fermentation-retarding effect and savory taste. The application of kugija extract could be domestically applied to improve the eating quality and the preservation of traditionally prepared Nabak kimchi.