Gviniashvili took the WBC Silver International title with a technical knockout after nine rounds, emerging victorious against Su, ranked third among China's domestic athletes.
Su suffered a brow injury after taking Gviniashvili's punch in round six, with the bleeding from the injury causing the Chinese boxer to abandon after three more rounds.
Gviniashvili and Cheng Su photographed during the weigh-in before the final. Photo: World Boxing Council.
For the 27-year old Georgian the fixture was his 15th international win through knockout, with 19 overall victories in 32 matches. Gviniashvili has also ended four matches in draw and conceded nine fixtures to his opponents.
The WBC Silver International final featured a high-profile attendance, with former world heavyweight world champions Mike Tyson and Evander Holyfield among the audience in Wuxi, China.
Gviniashvili is set to return to Tbilisi later today, with Professional Boxing Union of Georgia President Giorgi Kandelaki expected to welcome the winning boxer at the capital's international airport.
Born in north-east Georgia's Tianeti Municipality, Gviniashvili made his professional debut in the super welterweight category in 2008. The fixture against Cheng Su was the fifth competitive appearance for the athlete this year.