The purpose of this study was to investigate the quality characteristics of Jeung-Pyhn by the addition of chitosan-oligosaccharide (COS, Chitoligo-L). Jeung-Pyun is a traditional Korean fermented rice cake leavened by yeast. To develop a functional Jeung-Pyun, COS was added to the rice at the levels of 0, 2, 4 and 6% of the 2-hour-soaked rice. Physicochemical, sensory, rheological and inner structure characteristics of Jeung-Pyun were examined. The pH values of COS Jeung-Pyun batters were decreased with fermentation time. In sensory evaluation, the uniformity of the grain and overall quality of Jeung-Pyun added with 2% COS had the highest score among the samples. In He rheological properties measured with rheometer, the hardness of Jeung-Pyun with COS was higher than control. Cohesiveness of Jeung-Pyun added with 4% COS and gumminess, brittleness and springiness of Jeung-Pyun added with 2% COS were the highest among the samples. The inner structure observed by scanning electron microscope showed that Jeung-Pyun added with 2% COS had the largest and the most uniform air cells. In conclusion, Jeung-Pyun with 2% COS had positive effects on the qualify of Jeung-Pyun.