As Major General he served as the Commander Logistics Area Dhaka Cantonment of Bangladesh Army.

He served as Adjutant General of Bangladesh Army, Commandant of the Bangladesh Military Academy, the Director of Military Operations-Army headquarters and also the General Officer Commanding (GOC) of 55th Infantry Division and 17th Infantry Division.

After promotion to the rank of Major General he commanded 17 infantry division (Sylhet) from 2013 to 2016.

On 26 July 2016 UN Secretary-General Ban Ki-moon appointed Major General Mohammad Humayun Kabir as Force Commander of the United Nations Peacekeeping Force in Cyprus (UNFICYP).

He succeeded Major General Kristin Lund, the first female Force Commander in the UN.