Security forces have used teargas to disperse Ahly fans trying to enter the Arab Contractors Stadium, Al-Ahram's Arabic news website reported.
The Cairo arena is hosting the second-leg of the CAF Champions League final between Ahly and South Africa's Orlando Pirates on Sunday evening.
Police said they wanted to prevent ticketless spectators from entering the stadium.
A number of injuries and arrests have been reported.
"This gives a bad image for Egyptian football. I don't know why the crowd is doing this? Everything is well organised." the Egyptian Football Association (EFA) executive manager Tharwat Swailam told an Egyptian TV program.
"This would negatively affect Egypt World Cup playoff against Ghana," he added.
The national team is hosting Ghana on 19 November in Egypt in the second-leg of the Playoff after they lost 6-1 in Kumasi last month. Ghana has expressed security concerns over playing in Egypt due to the countries turbulent climate.
The African final is the first match to be open for maximum attendance since February 2012 when more than 70 Ahly fans died after clashes with rivals Masry following a league game.
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