كتب : Hatem Maher
"Mladenov is the new ENPPI coach. He will succeed Diaa Al-Sayed," the club said in a statement on their website.
"The Bulgarian tactician has penned a six-month deal with an option to extend it at the end of the season."
Rookie coach Al-Sayed took over at ENPPI in August after Anwar Salama handed in his resignation following some disappointing results in the African Confederation Cup and the Egyptian league.
However, the petroleum club hardly found consistency.
They exited Africa's secondary competition after losing to Stade Malien in the semi final and failed to impress in the league.
ENPPI, whose only trophy to date came in 2005 when they won the Egyptian Cup, lie fifth in the 16-team table on 21 points.
Saturday's 1-1 draw with Ittihad sealed Al-Sayed's fate to prompt the club to quickly name his replacement.
Al-Sayed will not leave the club though as he will be demoted to assistant coach, ENPPI chairman Maged Nagati told FilGoal.com.
Mladenov, who also managed Ahli Jeddah in Saudi Arabia, was sacked by Ettifaq in October after the team failed to grab any win in their first four league games.
He guided Bulgaria's CSKA Sofia to two league titles in 2003 and 2008.
The 52-year-old will lead ENPPI in the second half of the season after the league break.