Kim Dong-su () is a South Korean footballer who plays as a centre-back for Muangthong United in the Thai League 1.
In January 2014, moved from South Korea to Hamburg to the U-19 of Hamburger SV. After five junior Bundesliga games, he made the leap to the B-team, Hamburger SV II, half a year later and was there regulars of the strong regional league team, which marched unbeaten through the first round.
Kim joined J1 League club Omiya Ardija in 2017. On 6 June 2018, he debuted against AC Nagano Parceiro in Emperor's Cup.
On 31 January 2019, Kim moved to Germany again and this time, he signed with VfB Lübeck until June 2020.