The Parkhead side have reportedly made an offer of £3.5millon for the 19-year-old.
Hickey, following his debut campaign in Serie A, has attracted plenty of interest from Celtic as well as around Italy.
Napoli and Fiorentina have both been linked with moves for the Scotsman who played 12 times last season after moving to Bologna from Hearts for a deal which was worth £1.78million.
Bologna now value the versatile defender at £8million.
Celtic’s recent bid of £3.5million, according to reports in Italy, has been rejected with Bologna boss Sinisa Mihajlovic not keen to sell, especially if fellow left-back Mitchell Dijks is sold with interest from elsewhere in Serie A.
Why do Celtic want Hickey?
Hickey, a former youth player at Celtic before his move to Hearts, would bring new boss Ange Postecoglou flexibility.
At Tynecastle he operated mainly as a left-back, but also featured at right-back, as part of a back three and wing-back. He also played in the middle of midfield for younger age groups.
Hickey has experience of Scottish football and would likely hit the ground running and, on top of that, is at an age and has the potential to make the club lots of money if sold on once more.
Viewed as a future Scotland international, Hickey made a name for himself at the end of the 2018/19 season when he made two league appearances before starring in the Scottish Cup final against Celtic aged just 16.
It led to links with the likes of Manchester City.