This study was conducted to optimize the level of sugar added (20 (control), 15, 10, 5%) during the preparation of soy sauce-salted mushrooms (Pleurotus eryngii) jangachi without affecting the degree of preference. The salinity and sugar content during storage of soy sauce-salted mushrooms (Pleurotus eryngii) jangachi decreased significantly as the level of sugar added decreased. The moisture content was found to increase as the level of sugar added decreased. Additionally, the pH increased, while hardness decreased as the level of sugar added decreased during 3 weeks of storage. The L value (lightness) was not different from that of the control group until the addition of 10% sugar, while the a value (redness) and b value (yellowness) increased. The antioxidant activity of vitamin C content and DPPH radical scavenging activity increased as sugar content decreased. Upon sensory evaluation of mushrooms (Pleurotus eryngii) jangachi, the highest value in appearance was observed for the 5 and 15% treatments, while 5% had the highest flavor value, 15 and 10% had the highest taste values, 10 and 15% had the highest texture values, the control and 5% had the greatest clarification values, and the 15 and 10% groups had the greatest overall acceptance. These results suggest that a sugar level of 15% can be used without significantly affecting the overall acceptance.