Ahmad Shah ascended the throne on April 29, 1748, after the death of his father Muhammad Shah. He was only 23 years old at the time of his accession. At that time he had no experience in the field of administration, although he was the hero of the battle of Sarhind, in which he defeated Ahmad Shah Abdali. He failed to manage the affairs of the state. This led to the administration falling into the hands of his Wasir, Safdar Jang. The Wasir was also not capable to run the administration properly. In 1750, the Wasir joined the Marahtas against Ahmad Shah.
Ahmad Shah's short reign was a period of great disturbance. At this time the Rohillas started rebelling and Ahmad Shah Abdali invaded Punjab for the second time, and marched towards Delhi. In order to avoid the demolition of Delhi, Ahmad Shah made peace with Ahmad Shah Abdali by giving Punjab and Multan. Imad-ul-Mulk Ghazi-ud-Din, the grand son of Asaf Jah, assumed the office of Wasir due to the unfit leadership of Ahmad Shah. In 1754, Aziz-ud-din Alamgir captured Ahmad Shah, blinded and imprisoned with the help of Marahatas, and the second son of Jahandar Shah. He died on January 1, 1775, at Delhi.