Seongdong District consists of 20 administrative dongs (haengjeong-dong, 행정동)

• Doseon-dong (도선동 道詵洞)
  • Hongik-dong (홍익동 弘益洞): legal dong (beopjeong-dong, 법정동)
• Eungbong-dong (응봉동 鷹峰洞)
• Haengdang-dong (행당동 杏堂洞) 1∼2
• Geumho-dong (금호동 金湖洞) 1∼4
• Majang-dong (마장동 馬場洞)
• Oksu-dong (옥수동 玉水洞) 1∼2
• Sageun-dong (사근동 沙斤洞)
• Seongsu 1ga 1 dong (성수1가 1동 聖水1街 1洞)
• Seongsu 1ga 2 dong (성수1가 2동 聖水1街 2洞)
• Seongsu 2ga 1-dong (성수2가 1동 聖水2街 1洞)
• Seongsu 2ga 3-dong (성수2가 3동 聖水2街 3洞)
• Songjeong-dong (송정동 松亭洞)
• Yongdap-dong (용답동 龍踏洞)
• Wangsimni-dong (왕십리동 往十里洞) 1∼2
  • Sangwangsimni-dong (상왕십리동 上往十里洞): legal dong (beopjeong-dong, 법정동)
  • Hawangsimni-dong (하왕십리동 下往十里洞): legal dong (beopjeong-dong, 법정동)