Abbasi was born in Kazerun, Iran, on 11 July 1958. According to Mashregh News, an Iranian news website, he holds a PhD in nuclear physics.
Abbasi was a professor of nuclear physics at Shahid Beheshti University and has reportedly been a member of Iran's Islamic Revolutionary Guard Corps (IRGC) since the 1979 Islamic Revolution. He reportedly did nuclear research at the Atomic Energy Organization of Iran (AEOI). Prior to his appointment as head of the AEOI he chaired the physics department at Tehran's Imam Hossein University.
Abbasi was appointed head of AEOI by then President Mahmoud Ahmadinejad on 13 February 2011 to succeed Ali Akbar Salehi. The IAEA, the UN's nuclear watchdog, presented a report to its board in May 2011 that laid out new information on possible military dimensions of Iran's nuclear programme. The director of the IAEA, Yukiya Amano, wrote to Abbasi-Davani to reiterate the agency's concerns about the existence of a possible military dimension to Iran's nuclear programme and stressing the importance of Iran clarifying these issues.
The report stated:
"Based on the Agency's continued study of information which the Agency has acquired from many member states and through its own efforts, the Agency remains concerned about the possible existence in Iran of past or current undisclosed nuclear related activities involving military related organisations, including activities related to the development of a nuclear payload for a missile... there are indications that certain of these activities may have continued beyond 2004."
Abbasi was removed from office on 16 August 2013 and Salehi replaced him in the post.
Abbasi has regularly been linked to Iran's alleged efforts to make the nuclear weapon, a process called weaponization. According to an Institute for Science and International Security report citing an expert close to the International Atomic Energy Agency (IAEA), Abbasi was a key scientist in the alleged Iranian covert nuclear weapons program headed by Mohsen Fakhrizadeh-Mahabadi, a strong supporter of Iran's alleged nuclear weapons program. Abbasi personally directed work to calculate the yield of a nuclear weapon as well as work on high energy neutron sources, this expert added.
According to the same report, the IAEA had information that Abbasi was the head of the Institute of Applied Physics (IAP), which was a follow-on organization to the Physics Research Center. Both of the organizations acted as fronts for scientific work on a possible Iranian nuclear weapons program.
Abbasi is "listed in an annex to U.N. Security Council Resolution 1747 of 24 March 2007, as a person involved in Iran's nuclear or ballistic missile activities". This resolution imposes an asset freeze and travel notification requirements. Abbasi is described as a "Senior Ministry of Defence and Armed Forces Logistics (MODAFL) scientist with links to the Institute of Applied Physics, working closely with Mahabadi (also designated by the UN).
On 29 November 2010, Abbasi was seriously wounded and narrowly survived an assassination attempt on a Tehran street, as a man on a motorbike attached a bomb to his car as he drove to work. A separate similar bomb attack the same day killed another scientist, Dr. Majid Shahriari, who also taught at Shahid Beheshti University.