The Poland Under-19 international has been at the club since 2006 and was a regular feature for the Academy and reserve teams.
However, due to the experience Blues have in the goalkeeping department with Maik Taylor and Colin Doyle, Krysiak could not break into the first team and spent loan spells at York, Gretna, Swansea and Motherwell.
Academy manager Terry Westley said: "We couldn't guarantee that we wouldn't be in a very similar position next season in terms of Artur having to go out on loan again.
"We've already got two senior goalkeepers here, as well as young Jack Butland who is coming in and is somebody we think very highly of.
"So, for both Artur and ourselves it was really a decision made."