The man, identified by Egyptian security as El-Sayed Seliman, first approached Mr Mubarak's car as if he were trying to present a letter. He then rushed forward, wounding the President in the hand and slashing one of his bodyguards before he was killed.
An official statement said: "While President Hosni Mubarak was driving in the streets of Port Said, and, as he was waving with his arm outside the the car window, a man with a sharp weapon in his hand rushed towards him and inflicted a superficial wound."
The statement added: "Mubarak's guards acted promptly which led to his [the attacker's] death." On state television, which was showing crowds watching the motorcade, three shots could be heard. Mr Mubarak received medical treatment and went on to make a planned speech on the Egyptian economy.
Mr Mubarak became President of Egypt in 1981 when Anwar Sadat, his predecessor, was assassinated at a military parade in Cairo.
Meanwhile, in Israel police are holding five Israeli Arabs in connection with the two car bombs that exploded in Tiberias and Haifa on Sunday evening, killing three people. The dead men were all in the cars when they died and were probably victims of premature explosions.
It is the first time any of Israel's one million Arab citizens have been involved in a car bombing. Police have named the two men who blew themselves up in Tiberias as Amir Masalcha, 24, and Jad Azaiza, 23, both members of the Islamic Movement, a fundamentalist group in Israel.
The bomb attacks were clearly intended to undermine the Sharm el-Sheikh agreement signed by Ehud Barak, the Israeli Prime Minister, and Yasser Arafat on Saturday night in Egypt. But the political consequences in Israel will be less severe than they would have been had any bystanders been killed.
There was no claim for the attacks yesterday from Hamas or Islamic Jihad, which carried out a devastating bombing campaign in 1995-96. Islamic Jihad, always a small group, has been largely inactive since its leader, Fathi Shikaki, was assassinated by Israeli intelligence in Malta in 1995. Hamas, however, still has an organisation and has condemned the latest accord between Mr Arafat and Israel. It is possible it has turned to Arab Israelis, with Israeli citizenship, as well placed to evade Israeli or Palestinian intelligence surveillance.