The much-travelled former Tottenham and Middlesbrough man has signed a one year deal with the Tykes making them his fifth club in English football since arriving in 2005
The Tykes will be the 29-year-old's fifth English club in seven years after spells with Tottenham, Middlesbrough, Wigan Athletic and West Ham United.
He was released by boyhood club Zamalek in May after falling out of favour with boss Hassan Shehata following a dispute over wages but has now been given the chance to resurrect his career at Oakwell.
Mido has been dogged by fitness problems in the last three years but Barnsley manager Keith Hill believes they've acquired an "exceptional talent", although he admitted the player needs to work hard in order to get back up to speed.
"It's a great signing for the football club and for the profile of the club," Hill told the club's official website.
"I am looking forward to working with a player of exceptional talent. There will be plenty of work to be done and that will be a reflection of what we will see on match day. We can't wait to get going."
The Egypt international has 20 goals in 51 senior appearaces for the national team but hasn't featured for his country since 2009.
Mido netted 28 times in 141 games in England between 2005 and 2010 but failed to score for West Ham during an unsuccessful loan spell two seasons ago before re-joining Zamalek in Janaury 2011.
He is Hill's second signing of the week after former Chelsea youngster Jacob Mellis, who was infamously released after letting off a smoke grenade in the European champions' training ground in March, penned a two-year deal on Tuesday.