Prince Hamzah returned to Jordan in October 2000 as a Lieutenant in the Jordan Armed Forces. He was promoted to First Lieutenant in December of the same year, and served as a Platoon Leader and Division Commander. In June 2001, Prince Hamzah was promoted to the rank of Captain. In November 2004, Prince Hamzah was promoted to the rank of Major.

Prince Hamzah has always valued army service as a unique opportunity:  "You get to know people in Jordan from all different parts of the country, different social backgrounds, different perspectives on life. You get a feeling for the problems they face, the way they think, of their aspirations, their hopes and their lives."

For much of the year 2001, Prince Hamzah was stationed in remote desert areas and on field exercises with his men. In the summer of 2001, he also served with the Jordanian/ United Arab Emirates contingent of the UN Peace-keeping Force. Most recently, as Company Commander with the Second Battalion of the Fortieth Royal Armored Brigade, he was responsible for three platoons.