The 24-year-old, who has hit 26 goals in all competitions this season and is the Bulgarian top-flight's leading scorer with 16, was more than three times over the legal alcohol limit.
Dembele, nicknamed the 'goal machine' by local media, was also disqualified from driving in the European Union for nine months.
"He is a very intelligent boy," his lawyer Konstantin Simeonov told reporters in Sofia, adding the player had no restrictions over travelling abroad. "He just has to be very careful."
Dembele, who was born in a Paris suburb and represented France at junior level, is expected to make his Mali debut in Tuesday's friendly against Ivory Coast.
He received his first call-up by Mali coach Alain Giresse for a friendly in November but pulled out injured.
The eight-month sentence was suspended for three years and Dembele was ordered to pay minimal costs.
