| Honorific-Prefix: | Yang Amat Berbahagia Tun Datuk Seri Panglima |
| Ahmadshah Abdullah | |
| Native Name: | Malay: {{Script|Arab|أحمد شاه عبدﷲ |
| Order: | 9th Yang di-Pertua Negeri of Sabah |
| 1Namedata: | Chong Kah Kiat Musa Aman |
| Term Start: | 1 January 2003 |
| Term End: | 31 December 2010 |
| Chief Minister: | Chong Kah Kiat (2001-2003) Musa Aman (2003-2010) |
| Predecessor: | Sakaran Dandai |
| Successor: | Juhar Mahiruddin |
| Spouse: | Toh Puan Datuk Seri Panglima Dayang Masuyah Awang Japar |
| Birth Date: | 9 December 1946 |
| Birth Place: | Inanam, Jesselton, North Borneo |
Ahmadshah bin Abdullah (Jawi: أحمد شاه عبدﷲ; born 9 December 1946) is a retired Malaysian civil servant who served as Yang di-Pertua Negeri (Governor) of the state of Sabah from 2003 to 2010. He is currently a Pro-Chancellor of MARA University of Technology.
Ahmadshah began his education at Government Primary School Darau, Menggatal, Jesselton in 1952 and ended his secondary schooling in 1966 at La Salle Secondary School, Tanjung Aru, Kota Kinabalu. He received a Diploma in Development Administration from South Devon College in the United Kingdom and Bachelor of Science (Political Science) from Indiana State University in the United States.
He started his early career as a junior customs officer at the Royal Customs and Excise Department, Kota Kinabalu on 1 March 1968. Then, he was appointed as Executive Officer (Rural) and was moved to the Beaufort District Office as Assistant District Officer (Rural Affairs) on 10 November 1969. He was then seconded to the National Paddy and Rice Board as Chief Officer from April 1979 until July 1984.
In addition, he also worked as the Secretary of the Sabah State Public Service Commission (August 1984 to October 1986), Dakwah Officer of Sabah Islamic Affairs Council (October 1986 to January 1988), Secretary of Islamic Council of Sabah (January 1988 to June 1994), Secretary to the Internal Affairs and Research Office of Sabah (1994 to 1995) and was later promoted as the Director of the Sabah State Public Service Department (December 1995 to March 1997). His final position before his retirement and later appointment as governor was Deputy State Secretary (Administration) from 22 March 1997 to 29 November 2002.[1]
On 1 January 2003, he was sworn in as the ninth Yang di-Pertua Negeri of Sabah (by then he was already retired from government service since the end of 2002, in which he chose the optional retirement age of 56). He served two full terms and stepped down on 31 December 2010.
He is married to Hajah Dayang Masuyah binti Awang Japar (1948-23 March 2020) and the couple are blessed with three sons and a daughter as well as nine grandchildren.[1]