Boakye-Yiadom started his career with West Ham United and Barnsley, for whom he made two first-team appearances in 2014/15.
He joined Leatherhead after returning to London from Yorkshire and then had a spell with Waltham Forest.
But he made only one competitive appearance for Forest, scoring in the 2-2 draw with Hullbridge Sports on the opening day of last season, before joining Dulwich Hamlet.
He played thirty-five times for the Bostik Premier runners-up and also had a nine-game loan spell back at Leatherhead where he played under new Concord Rangers management team of Sammy Moore and Jack Midson.
And Midson said of the signing: "Nana is a very quick and powerful forward who strikes fear into defenders. He has a point to prove next year".