After graduating from King Fahd University of Petroleum and Minerals in 1978 (1398H), Eng. Mohammed bin Abdullah Al-Quwaiz began his professional career as an engineer at the Research and Industrial Development Center of Al-Dar Saudi Consulting Services Company, where he served from 1978 to 1982 (1398H–1402H).

He then held the position of General Director of Projects and Maintenance at the Ministry of Health from 1982 to 1998 (1402H–1418H).

In 1999 (1419H), he was appointed General Director of the Water and Wastewater Authority. In the same year, he also served as a member of several committees and administrative councils, including the Water and Public Utilities Committee and the Saudi–Japanese Joint Committee.

Later, Eng. Al-Quwaiz served as a member of the Shura Council from 2002 to 2013 (1422H–1434H). During this period, he chaired several specialized committees and presented a number of proposals, such as the Housing Authority Law, the Small and Medium Enterprises Authority Law, the Saudization of maintenance and operation contract jobs, and the proposal for issuing the Engineers’ Cadre, among others. He also contributed additional recommendations through reports on government entities.

He then assumed the role of Mayor of the Holy Capital (Makkah), where he supervised the implementation and follow-up of numerous projects and initiatives aimed at developing the Holy City.