Pisa confirmed on Friday that the famously hot-tempered 38-year-old had agreed to return and would take charge of his first training session in the afternoon.
Gattuso led Pisa to promotion from the third tier last season after winning a two-leg playoff against Foggia and said it was as good as winning the Champions League with Milan.
But he quit on Aug. 1, saying there were "problems on a daily basis" and that the club lacked passion.
Gattuso's coaching career has been a mixed bag, although never dull.
He began at Swiss first division side Sion in 2013 but was sacked after three months, then joined Italian Serie B side Palermo where he was fired after six games.
In 2014, he tried his luck with Greek Super League side OFI Crete who were beset by financial problems and, according to Gattuso, were "struggling to feed their players".
He lasted six months, during which he gave an infamous expletive-ridden news conference in which he banged his fist on the table repeatedly and said, in broken English, that he expected his players to "play with balls" despite the problems.
Almost always dressed in black, Gattuso's touchline ranting became a feature of Lega Pro last season, including one incident where he slapped a member of his own coaching staff.
(Writing by Brian Homewood, editing by Ed Osmond)
