[7] Bykov's father was a military and intelligence officer of mixed Polish-Czech ancestry originally named Semyon Geronimovich Gordanovsky.

He was later promoted to a high-ranking position in the Communist Party of the Soviet Union and served as a managing director at various enterprises.

In 1939 he joined a youth theatrical studio organized by a Pioneers Palace where he met Alexander Mitta, Boris Rytsarev and Igor Kvasha.

During the Battle of Moscow his family was evacuated to Yoshkar-Ola for three years, although his father chose to stay and volunteered for the front line.

In 1947 he entered the Boris Shchukin Higher Theater College to study acting under Vera Lvova and Leonid Shikhmatov.

[6] In 1951 Bykov graduated and immediately joined the Moscow Youth Theater where he served as an actor and a stage director until 1959.

In 1959 he played the main part of Akaki Akakiyevich in The Overcoat, an adaptation of Nikolai Gogol's story directed by Aleksey Batalov.

He played over 100 roles and became highly popular as a comedy actor with such roles as Chebakov from Balzaminov's Marriage (1964), Barmalei from Aybolit-66 and Skomorokh from Andrei Rublev (both 1966), Ivan Karyakin from Two Comrades Were Serving (1968), Petrykin from Big School-Break (1973), Cat Bazilio from The Adventures of Buratino (1975), Father Fyodor from The Twelve Chairs (1976) and others.

His films are generally associated with postmodernism, presented as a mix of different styles, genres and techniques, with theatrical musical numbers, arthouse editing, fourth wall breaking and so on.

An unexpectedly grim Scarecrow released in 1984 became especially controversial and led to a lot of public criticism; some insisted it should be banned.

During the 1995 Parliamentary elections he headed a liberal pro-government Common Cause party along with Irina Khakamada and Vladimir Dzhanibekov.

Bykov adopted her son from her first marriage to Pavel Sanayev (born 1969), who became a popular Russian film director and writer.

[18][19] In 2010 his widow Elena Sanayeva published a book of Bykov's diaries (from 1945 to 1996) that contained a lot of personal thoughts along with his wife's commentaries.

In his interview to Vladislav Listyev he stated that modern cinema was solely built around money, or the golden calf as he called it, with no place for art.