Hannam Bridge, Road bridge in Seoul, South Korea

Hannam Bridge is a girder bridge over the Han River in Seoul, linking Sinsa-dong in Gangnam District with Hannam-dong in Yongsan District. Its two parallel decks together measure 919 m long and 51.2 m wide, carrying 12 lanes of traffic. The older upstream deck is a three-span continuous steel plate girder structure on 27 reinforced concrete piers, while the downstream deck added in 2001 is a steel box girder.

Construction began in 1966 under Hyundai Engineering and was completed in 1969, initially named the Third Hangang Bridge. The structure was renamed in 1985 and became part of international highway networks linking several Asian countries.

The bridge's old name, Third Hangang Bridge, was popularized by Hye Eun-Yi's 1979 disco song "Jesamhanggyo". Some lyrics were rewritten at the time as decadent, and Hye restored the original words on her 2007 album. In 2013 the bridge was listed as Seoul Future Heritage No. 2013-276.

The bridge carries twelve lanes of traffic and is one of the busiest crossings over the Han River, with about 196,500 vehicles daily in 2023. There is an elevator at the southern end. It links to the Gangbyeon Expressway and Olympic Expressway via ramps.

The bridge's 1966 design was widened from four to six lanes after an official argued it should be at least one metre wider than a 25-metre bridge in Pyongyang. The change forced engineers to adapt foundations already sunk 15 metres deep.