The Portuguese tactician will take the reins in the Korean capital from January.
The 56 year-old has experience in Portugal as well as with Asian national teams like Saudi Arabia and Jordan and club teams such as Persepolis in Iran.
Seoul finished third in the regular K-league season in 2009 and are looking to win a first domestic title and then to get back into the Asian Champions League.
“FC Seoul has the potential to be the No. 1 team in the K-League and Asia. I will make this team a top side in Asia as soon as possible,” Vingada told the club’s official site.
After three seasons, with the club Gunes returned to Turkey in November, to take the reins of Trabzonspor once again.