In 1981 he had graduated with honours from the Far Eastern State University Faculty of Law. Has been teaching and conducting research. Headed the Far Eastern State University Faculty of Law; later became the first deputy director of the Law Institute of the University.
In 1995-2008 Sergey Knyazev had served as a head of the Primorsky kray Electoral Commission. Led the working panel, which drafted the Charter of Primorsky territory.
Has authored and co-authored more than 300 publications on various issues of constitutional, administrative, municipal and other fields of law.
Lawyer Emeritus of the Russian Federation. Honoured Scientist of the Russian Federation.
A Judge of the Constitutional Court since October 2008.