Gangil-dong (Korean: 강일동) is a dong (neighborhood) of Gangdong District, Seoul, South Korea.

Gangil-dong is located on the easternmost side of Seoul. Originally a small farming village where development was prohibited due to its location at Seoul's greenbelt, the city's new developments projects in the 21st century lead to a complete transformation of this neighborhood. It is now home to the Gangil River Park multi-rise apartment complexes with a view into the Han River, the Gangil High-Tech Business Center, a brand new library and a new four-lane bridge connecting it to Sangil-dong.