Muhammad Awad Tag al-Din said on Saturday on state television that doctors in Munich, Germany, had operated on Mubarak, 76, to correct a slipped disk.
"A successful operation was carried out this morning for Mr President," Tag Eddin said from Germany.
Dr Michael Mayer, the surgeon in charge of the German medical team that performed the surgery, said: "There were no complications or problems during the surgery" and that Mubarak will be starting to walk on Sunday.
It has been rare for state media to report on Mubarak's health, but since going to Germany for back treatment, there have been regular updates broadcast apparently to reassure Egyptians that the president was not seriously ill.
In November, the president interrupted a speech to parliament for 30 minutes, suffering a cold and a slight drop in blood pressure. The interruption caused a brief political scare as Mubarak - who has ruled Egypt since 1981 - does not have a designated successor.
In early July, he is scheduled to appoint a new government.
Mubarak's wife, Suzanne, and sons Gamal and Alaa, accompanied the president to Germany, who arrived in the European country on 20 June. It was unclear when he would be able to return to Egypt.