Sun sets on Stoichkov job in South Africa
The 44-year-old Bulgarian joined the side in July and led them to second place in the league which ended earlier this month, but after hinting several times at his desire for a new contract, he finally announced his decision to resign.
"I won't be coaching this team next season because I have not been given a contract. I had a meeting with the president and I have reached a conclusion," he told a radio sports show.
Owned by billionaire mining magnate Patrice Motsepe, the club has spent liberally on players in a bid to win the title and said a new three-year contract had been offered to Stoichkov in January but subject to his winning the league.
Sundowns finished a point behind SuperSport United in the standings but are still involved in two cup tournaments, although it remains unclear whether Stoichkov will stay on until his one-year deal ends in June.
Stoichkov was the 1994 European Footballer of the Year and enjoyed successful spells with Barcelona and Parma but has had a checkered career as a coach since ending his playing days.