Lieutenant Colonel Pg Siti Khatamalzariah bte Pg Haji Kamaludin enlisted into the Royal Brunei Armed Forces (RBAF) on 18th April 2005. She was later commissioned as an Officer on 09th Dec 2006 after completing her Officer Cadet training at the Officer Cadet School SAFTI MI, Singapore.
Throughout her service, Lieutenant Colonel Pg Siti Khatamalzariah has held various staff appointments. Her appointments include Research Officer, Directorate of Intelligence, Assistant Training Officer, Training Officer at the Officer Cadet School, Staff Officer Grade 3 Training, Staff Officer Grade 2 Training under the Directorate of Personnel and Academic Advisor I, Defence Academy Royal Brunei Armed Forces. She was the first female officer posted to hold the post as an Assitant Training Officer at the Officer Cadet School since its establishment in August 2008. Lieutenant Colonel Pg Siti Khatamalzariah assumed the appointment of the Commanding Officer on 1st September 2020, becoming the 7th Commanding Officer, OCS DA RBAF. She also became the first woman to hold the appointment as Commanding Officer OCS.
She has attended various military courses locally and overseas throughout her service. Among the courses she attended were Basic Manpower Officer Course (Singapore), Basic Logistics Course (Singapore), Junior Staff Course (Brunei), Excellence in Curriculum Implementation through Visionary Leadership and Situational Supervision (Brunei), IOSH International Management Safety (Brunei), Basic Internal Auditing (Brunei), Advanced Manpower Officer's Course & Advanced Logistics Officer's Course 2 (Singapore) and the 49th Goh Keng Swee Command and Staff Course (Singapore).
Lieutenant Colonel Pg Siti Khatamalzariah graduated from Universiti Brunei Darussalam with Bachelor in Education (Hons). She was honored with Pingat Laila Tugas, Pingat Jubli Emas and Pingat Indah Kerja Baik (P.I.K.B). She is married to Pg Haji Wijaya Kesumadi bin Pg Haji Mohd Alli and blessed with two daughters, Dk Siti Sayyidatun Wajiihah and Dk Syifaa Kayyisah. She enjoys running, swimming and travelling in her spare time.