Lieutenant Colonel Haji Mohammad Shanonnizam bin Sulaiman joined the Royal Brunei Armed Forces on 12 July 1996. He began his career serving as an Infantry Platoon Commander in 'A' Company, 3rd Battalion Royal Brunei Land Force on completion of his officer cadet training at the Royal Military Academy Sandhurst, United Kingdom in April 1998.
Throughout his military career, Lieutenant Colonel Haji Mohammad Shanonnizam has held various staff and command appointments. Trained as a Signal Officer at Warminster United Kingdom in 2000, he served as a Regimental Signal Officer in 2nd Battalion Royal Brunei Land Force and as SO3 Communication at the Royal Brunei Land Force Headquarters. He commanded 'B' Company, 1st Battalion Royal Brunei Land Force in 2003 and had the honour to serve as an Aide de-Camp to His Royal Highness the Crown Prince. He served as SO2 Communication at the Directorate of Operations and as SO2 C41 at the Directorate of Force Capability Development and played a key role in the digitisation of the Armed Forces' radio communication system in 2007.
Upon completion of his Command and Staff Course at the Australian Defence College in 2009, he commanded the Officer Cadet School, Royal Brunei Armed Forces after a short stint as SO2 Intelligence at the Royal Brunei Land Force Headquarters. Then, he served as SO1 Communications Information Systems at Joint Force Headquarters (JFHQ), as SO1 Land Capability Development at the Directorate of Force Capability Development and he commanded 3rd Battalion Royal Brunei Land Force from January 2015 to Jun 2017.
He became the Chief of Staff of Royal Brunei Land Force on 30 July 2020 after completing his three years tour as Defence Adviser to the United Kingdom and non-resident Defence Attache to the Republic of France and Federal Republic of Germany.
In recognition of his service, Lieutenant Colonel Haji Mohammad Shanonnizam was awarded The Most Honourable Order of Setia Negara Brunei 4th Class (PSB) in 2006 and The Most Honourable Order of Seri Paduka Mahkota Brunei 3rd Class (SMB) in 2017 by His Majesty the Sultan and Yang Di-Pertuan of Brunei Darussalam.
Lieutenant Colonel Haji Mohammad Shanonnizam is married to Pg Hajah Rozedah binti Pg Haji Sulaiman and blessed with one son. He enjoys reading and playing golf in his spare times.