Vieira is the second Brazilian star to arrive at Simba after Wilker Henrique da Silva was signed five days ago.
"Another player from Brazil with the huge ability to play at centre-back and in deep-midfield, Gerson Fraga Vieira has signed a two-year deal with Champions Simba," the club announced on their Twitter handle.
Mchezaji mwingine kutoka Brazil mwenye uwezo mkubwa wa kucheza nafasi ya beki wa kati na kiungo mkabaji, Gerson Fraga Vieira (26) amesaini mkataba wa miaka miwili na Mabingwa wa nchi. pic.twitter.com/hNcAusfciB— Simba Sports Club (@SimbaSCTanzania) June 25, 2019
Vieira has played for 10 clubs in his career, always signing short-term contracts and Simba will be his first African club after spending time mostly in his native country.
Gerson has been capped at junior level for his country where he played and won the Mediterranean International Cup with the U15's in 2009. He also played for the U17 team.
"Vieira has captained Brazil's U17, a team that boasted players like Neymar, Coutinho, Casemiro and goalkeeper Alisson (Becker). He also played for the national U20 team and has now joined the champions from ATK FC of India," the club's statement further read.
"It is now time that we compete with the African giants for the Caf Champions League title and we will surely need the precision and power offered by Gerson Fraga Vieira."
Meanwhile, Shiboub Ali Abdalrahman has also been signed by the Tanzanian side from Al Hilal of Sudan for one year.
Finally, assistant captain Mohamed Hussein extended his Simba stay for another two years.