There is no difference; they are exactly the same Palestinian Leader. Mahmoud Abbas is his real name and Abu Mazen is his nickname.
Mahmoud Abbas, often referred to by his nickname "Abu Mazen", is the current President of Palestine as of July 2014.
Mahmoud Abbas AKA Abu Mazen. He orchestrated the munich massacre and has been involved in many terrorist operations.
Primarily Yasser Arafat, but since his death, there has been Mahmoud Abbas / Abu Mazen in the West Bank and Ismail Haniyeh in the Gaza Strip.
The cast of Marrow - 2012 includes: Mazen Abbas as None Nesrin Fandi as None
The Arab-Israeli Conflict has gone on for the entire length of Israel's existence (64 years). Therefore a list of the leaders of the Arab-Israeli Conflict would be very long. Currently, Israel is headed by Prime Minister Benyamin Netanyahu, the Palestinian Authority is headed by Mahmoud Abbas (Abu Mazen), and Hamas is headed by Khaled Meshaal.
Mazen Dana died in 2003.
Mazen Dana was born in 1962.
Mazen Mneimneh was born in 1986.
Mazen Abdul-Jawad was born in 1977.
Mazen Asfour was born on 1953-06-22.
Mazen al-Tumeizi died in 2004.
Mazen is Arabic in origin meaning "storm cloud". Mazen may also be Persian in origin from the Avestan mazainya meaning "giant".