Ghasemi joined the Army of the Guardians of the Islamic Revolution (IRGC) in Kharg Island in 1979. He participated in the Iran-Iraq War. After the war, he joined the Khatam Anbia troops in Bushehr, the Guards' engineering and construction company. In 1996, he was named head of the IRGC navy's Nouh base. Ghasemi became deputy commander of the troops in 2001.
He was the chair of the IRGC-affiliated Khatam-ol Anbiya Construction Headquarters from 2007 to 2011. He retired from the military in August 2011.
On 26 July 2011, he was nominated as oil minister by Mahmoud Ahmadinejad to succeed Masoud Mir Kazemi. He was approved by the parliament on 3 August 2011, being the fourth oil minister in the Ahmedinejad government. He received 216 for votes of the 246 Majlis members. He was the President of the OPEC for 2011. Ghasemi's tenure as oil minister ended on 15 August 2013 and he was replaced by Bijan Namdar Zanganeh in the post. Shortly after leaving office Ghasemi was appointed advisor to Defense Minister Hossein Dehghan on 22 August.