In 1971, he graduated from the University of Ceylon Colombo campus, with a Bachelor of Laws Degree (LLB) winning the Gate Mudaliyar Edmund Pieris prize awarded for academic excellence, and after passing the Final Examination at Sri Lanka Law College for the Admission of Advocates held in October 1973, was admitted to the Bar as an Attorney-at-law of the Supreme Court of Sri Lanka in June 1974.
Being a prolific writer, Marsoof is the principal editor of the volume entitled In Pursuit of Justice: Corde Et Amino and the author of the book The Quazi Court System in Sri Lanka and its Impact on Muslim Women.
He regularly addresses the International Symposium on Economic Crime organised by Jesus College, Cambridge and was invited to make the Dr. A. M. A. Azeez Memorial Oration in 2002.
He delivered a large number of landmark judgments particularly on constitutional and administrative law issues during his very short stay at the helm of the Court of Appeal.
Apart from his judicial work, Marsoof has been involved in social mobility and law reform initiatives, and is currently the Chairman of the Committee appointed by the Government to suggest amendments to the Muslim Marriage and Divorce Act in force in Sri Lanka.