In order to improve functionality of kochujang which is one of the traditional foods of Korea, sea tangle powder(2, 4, 6 and 8% sea tangle powder on the glutinous rice weight basis) was added to the raw material of kochujang and then investigated the change of physiochemical properties with control kochujang during the fermentation at 3$0^{circ}C$ for 120 days. During 120 days fermentation, moisture and crude protein contents were gradually decreased with fermentation time, whereas crude fat content NaCl were slightly increased with fermentation time. The contents of reducing sugar of sea tangle kochujang was rapidly increased until 60 days of fermentation after that it was increased slightly up to 90 days of fermentation to the highest value and then reduced slightly or not changed approximately until 120 days. pH was reduced up to 60 days of fermentation after that it remained 4.63~4.91 in 90~120 days. Acidity was increased with fermentation time, and it was the highest value of 11.5~12.4$mell$ in 120 days of fermentation. Viscosity was increased with increased with fermentation time. Especially a case of additional sample of 8% sea tangle powder was highly increased until 60 days. A case of color difference value, in initial time of preparation of kochujang was distinct difference of value for additional samples respectively but as the fermentation progressed, among the samples not found consistent change of color difference value. L value was gradually decreased during fermentation. A value was decreased up to 30 days of fermentation and it was increased again totally at 60 days of fermentation. B value was decreased totally at initial time of fermentation and a case of control was increased again at 90 days of fermentation, the other samples increased again 60 days earlier than 30 days.