This study investigated the physicochemical characteristics and antioxidant activities of buckwheat soksungjang and commercial doenjang. We analyzed moisture, total sugar, color, salinity, amino type nitrogen, amino acids, and antioxidant activities. Buckwheat soksungjang had lower salinity content (7.44±0.10%) than commercial doenjang (8.82-9.81%). The quercetin content of buckwheat soksungjang was 0.78±0.01 mg% while commercial doenjang’s was 0.29-1.16 mg%. The DPPH and content of the total polyphenol of buckwheat soksungjang (DPPH radical scavenging activity 62.21±0.45% and total polyphenol content 447.51±14.61 mg%) and commercial doenjang (DPPH radical scavenging activities: 44.07-68.50%; total polyphenol contents: 328.26-407.51 mg%) were both significant.