| Honorific Prefix: | Dato Paduka |
| Matussin Omar | |
| Honorific Suffix: | DPMB SMB SNB PJK PKL |
| Office: | 3rd Director of Brunei Museum |
| Term Start: | 1987 |
| Term End: | 1995 |
| Deputy: | Lim Jock Seng |
| Predecessor: | Matassim Jibah |
| Successor: | Lim Jock Seng |
| Birth Date: | 1948 11, df=yes |
| Birth Place: | Sumbiling Lama, Brunei Town, Brunei |
| Awards: | Mastera Literary Award |
| Alma Mater: | University of Malaya (BSc) Australian National University |
| Education: | Sultan Omar Ali Saifuddien College |
Matussin bin Omar (born 16 November 1948), pen name D. P. Matussin, is a historian, civil servant and writer from Brunei who previously served as the third director of the Brunei Museum from 1987 to 1995. He started writing poetry, short tales, essays, and song lyrics in 1962. Since then, he has established himself as a well-known scholar of Bruneian literature and culture.
Matussin bin Omar was born in Kampong Sumbiling Lama on 16 November 1948. Early education was obtained at Sultan Omar Ali Saifuddien College (SOASC) from 1959 to 1968 and Sultan Muhammad Jamalul Alam Malay School from 1955 to 1958. He continued his education at the University of Malaya in Kuala Lumpur from 1969 to 1973, earning a Bachelor of Science (BSc) degree in Sociology and Anthropology. In 1976, the government of Brunei sent him to the Australian National University in Canberra as part of the In-Service Training Scheme, where he earned a Master's degree in Prehistory in 1979.
Matussin began employment in SOASC as a teacher. He transferred to the Department of Museums at the end of 1973 and took a job there as an Archaeological Officer. He was named Curator of Archaeology in 1977. He served as the Department of Museums' Deputy Director from 1 January 1983 until 1987. In 1987, he was named Director of Brunei Museum, a role he maintained until 1995.
Matussin was hired on 4 December 1995, by the Ministry of Youth, Culture and Sports (MCYS) as a Special Duties Officer. He was selected as the Chef De Mission for the Brunei delegation in the 1997 SEA Games, which were held in Jakarta, Indonesia. Additionally, he served as the MCYS' Permanent Secretary. In addition to his writing career, he has been penning song lyrics for events such as Family Day and International Museum Day, when Brunei celebrated at the Brunei Museum.
Matussin's works and monographs include:
Matussin was awarded the 2012 Mastera Literary Award for his work, Book: Biarkan kami bernafas . 2009 . 978-99917-0-665-8 . ms . Omar . Matussin bin . Dewan Bahasa dan Pustaka Brunei, Kementerian Kebudayaan, Belia dan Sukan .
See main article: Orders, decorations, and medals of Brunei. Matussin has earned the following honours: