Datuk Seri Panglima Sulong Bin Matjeraie pursued his studies at University of Malaya, Kuala Lumpur in 1966 and was conferred the Bachelor of Arts (Honours) Degree in 1969. In 1971, he read Law at the Inns of Court School of Law, London and in July 1974 he was called to the Bar of England and Wales by the Honourable Society of Inner Temple, London. In the same year he was also admitted and enrolled as an Advocate to the High Court of Borneo at Kuching.

In 1975, he left to study at the University of Southampton, England and was conferred with a Master of Laws Degree in Mercantile Law in 1977. In 1978, he attended a course in Advanced Management Programme jointly sponsored by Universities of Alberta, British Columbia, Manitoba, Saskatchewan, Canada and was awarded a Certificate in Advanced Management Programme (AMP) by the Banff School of Advanced Management.

In 1977 he was appointed as the Administration & Finance Manager at the Sarawak Timber Industry Development Corporation before assuming the General Manager role from 1979 and 1980. He became the General Manager of Bintulu Development Authority in Bintulu that same year until 1983.

He left the Government Service in 1983 to set up his own legal firm under the name of Messrs Sulong Matjeraie & Co. in Kuching, Sarawak and left the firm in 2000. In 1998, he was appointed as a Judicial Commissioner of High Court Johor Bahru until his appointment as a High Court Judge of Malaya at Johor Bahru, Johor in June 2000 and at Kota Kinabalu, Sabah, in July 2000. He subsequently served as a Court of Appeal Judge Malaysia from 2007 to 2012 and finally as Federal Court Judge Malaysia in 2012 until he retired in January, 2013.

He was later appointed by the Prime Minister of Malaysia as one of the four (4) eminent persons to serve in the Judicial Appointments Commission for a period of two (2) years commencing from 10th February, 2013.