Mark Spitz managed to win only 7 of them in Munich. Phelps also holds the absolute record in the total number of Olympic golds in his career with 28 of them, 23 of which are gold.
Michael Phelps won his eighth gold medal at the Beijing Olympics on August 17, 2008. He thus became the record holder for the number of gold medals won at one Olympic Games. Namely, no one else managed to win eight gold medals at any of the Olympic Games. Mark Spitz managed to win seven of them in Munich in 1972.
In addition, Phelps holds the absolute record in the total number of Olympic golds in his career with 28 of them, 23 of which are gold.
At these 2008 Beijing Olympics, Michael Phelps won gold medals in:
100 meters dolphin
200 meters dolphin
200 meters free
200 meters mixed
400 meters mixed
4 x 100 meters free
4 x 100 m mixed
4 x 200 m freestyle