Iran Jews express Holocaust shock
In a letter to the president, Haroun Yashayaei said the leader's remarks had shocked the international community and caused fear in Iran's Jewish community.
Mr Yashayaei described the Holocaust as one of the most obvious and sad events in the 20th Century.
Six million Jews were killed in Nazi persecution during World War II.
This is the first time that a senior Iranian Jewish leader has openly criticised President Ahmadinejad for denying the Holocaust.
In his strongly-worded letter, Mr Yashayaei asked the president how he could justify what he termed the crimes of Hitler.