Graduated from high school with a gold medal. Entered without exams and studied at the Faculty of Law of Leningrad University named after A. A. Zhdanov. While studying at the university, he participated in productions of the Theater-Studio of Leningrad State University under the guidance of actress and teacher Evgenia Karpova. In 1955, after the 3rd year of law school, he entered the acting faculty of the Leningrad Theater Institute named after A. N. Ostrovsky (Leonid Makaryev's course). After completing the 2nd year, in 1957, Sergei Yursky was invited to the Gorky Bolshoi Drama Theater. From the mid-1960s he was one of the leading actors of the Tovstonogov troupe; among his best roles were Chatsky, Tuzenbach, Aesop in "The Fox and the Grapes" by G. Figueiredo, Professor Polezhaev in "An Uneasy Old Age" by L. Rakhmanov. Here Sergei Yursky also made his debut as a director, staging in 1974 the play "Moliere" based on M. Bulgakov. The actor gained wide fame for his roles as Vikniksor in Gennady Poloka's film "The Republic of ShKID" (1966) and Ostap Bender in "The Golden Calf" (1968) by Mikhail Schweitzer.

He performed as a reciter with programs (fifteen in total) of classical and contemporary authors. In 1978 Sergei Yursky moved to Moscow and became an actor, and later also a director of the Mossovet Theater. From 1991 he simultaneously acted and staged performances at the "School of Modern Play" theater. The novella "Chernov", written by him in the mid-1970s, became the literary basis for his directorial debut in cinema in 1990 ("Chernov"). From 1996 he was a member of the board of trustees of the St. Philaret Orthodox Christian Institute. In 2011 he became a laureate of the "Star of the Theatergoer" award. Sergei Yursky was the author of several books of prose and plays written under the pseudonym Vatsetis. He died early in the morning on February 8, 2019 in Moscow in a hospital at the age of 83. His daughter Darya cited cardiac arrest after a long illness as the cause of death.