The declaration by Sheikh Abdel Hamid al-Atrash, who heads Al-Azhar University's committee for fatwas or religious rulings, comes after similar rulings by religious leaders in Saudi Arabia and Turkey.
"A wife has the legitimate right to hit her husband in order to defend herself," Atrash was quoted as saying.
"Everyone has the right to defend themselves, whether they are a man or a woman... because all human beings are equal before God," he said.
Over the last few days, Saudi Sheikh Abdel Mohsen al-Abyakan stressed the fact that a wife should resort to "the same kind of violence" as her husband used against her, whether it be with a leather strap or a wire cable, the paper said.
Prominent Turkish Muslim preacher and writer Fethullah Gulen went one step further and ruled that a woman should return the violence with interest.
"She should give back two blows for each one received," the paper quoted him as saying.
Rights groups quoted by Amnesty International say that 35 percent of Egyptian women killed each year die as a result of domestic violence.