The 40-year-old former Brazil international, whose past clubs also include Real Madrid and Manchester City, was found guilty of involvement in the gang rape of a 23-year-old Albanian woman.
The incident occurred in a Milan night club on January 22, 2013.
The conviction was upheld by Italy’s supreme Court of Cassation in 2022, making it definitive.
Brazil does not extradite its nationals, but courts sometimes order that sentences passed down abroad are served there.
Robinho, 38, played for Milan between 2010 and 2014, scoring 25 goals in 108 appearances.
He has 100 Brazil caps and 28 goals for his country.
ANSA