The winger has signed for the Foxes on a five-year deal and has joined the Leicester squad in Stockholm, where they will play Barcelona in a friendly.
The deal had been expected to take place for some time, with the Poland international already speaking as if he had signed a deal with the Premier League champions last week.
Kapustka played 65 times for former club Cracovia Krakow and also has 11 caps for Poland at the tender age of 19.
Welcome to Leicester City, Bartosz Kapustka!
— Leicester City (@LCFC) August 3, 2016
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