The 28-year-old made just 13 appearances across all competitions in his solitary season at the King Power Stadium, having failed to displace Kasper Schmeichel as the club's number one goalkeeper.
Zieler has left the club's training camp in Austria to complete the move, signing a three-year deal with the newly-promoted German outfit.
"Leicester City have today agreed the transfer of goalkeeper Ron-Robert Zieler to VfB Stuttgart," read a statement on the club's official website.
"Ron travelled from City's pre-season training camp in Austria to Germany on Tuesday to finalise personal terms and complete a medical, before signing a three-year deal.
"He departs with the thanks and best wishes of everyone at Leicester City."
The move sees Zieler return to the Bundesliga having joined Leicester from Hannover just last summer.