Daihōji Sumiuji served as a bushō during the Sengoku period. He was the thirteenth head of the Daihōji clan.
Sumiuji was born as the son of Daihōji Masauji. He received one of the characters in his name from Ashikaga Yoshizumi, the eleventh shōgun of the Muromachi bakufu.
In the era of Sumiuji, relations deteriorated with the Sagoshi clan who served as the governors of the Akumi District in Dewa Province.
In 1512, Sagoshi Ujitaka invaded the Tagawa District in the territory of the Daihōji. The ensuing conflict resulted in over 1,000 casualties from both sides while Sumiuji suffered a bitter defeat. In 1513, after Ujitaka launched a second invasion, Sumiuji defeated the aggressors while both Ujitaka and his son were killed.
Sumiuji did not have children so, after his demise, the headship of the clan was inherited by his younger brother, Daihōji 氏説.