The 22-year-old has agreed to join the Silkmen for the remainder of the 2017/18 campaign with a view to earning a deal with the club for next season.
De Girolamo started his career at Sheffield United and had three spells on loan at York City and a stint at Northampton Town during his time there.
He joined Bristol City in the summer of last 2016 and went on loan to Cheltenham Town last season, scoring a hat-trick in a Checkatrade Trophy tie against Leicester City under-23s.
The striker, who has been capped at youth level by Italy, spent the first half of this season with SkyBet League Two side Chesterfield but after returning to Ashton Gate he parted company with City and will now link up with John Askey’s promotion-chasing side for the remainder of the season.