Koshiro Shimada (?? ???, Shimada Koshiro, born September 11, 2001) is a Japanese figure skater.
He is the 2019 Bavarian Open senior champion and the 2018–19 Junior Grand Prix Final bronze medalist.
He has won three other medals on the ISU Junior Grand Prix series (silver at the 2018 JGP Austria, bronze at the 2016 JGP France and 2018 JGP Slovenia).
He placed 14th at the 2017 World Junior Championships and is a two-time Japan Junior national medalist.