Sidelnikov studied with E. O. Messner and Yuri Shaporin at the Moscow Conservatory. He taught at the Moscow Conservatory where he was a professor from 1981. Among his pupils were Audronė Žigaitytė, Vyacheslav Artemov, Eduard Artemyev, Dmitri Smirnov, Vladimir Tarnopolsky, Vladimir Martynov, Anton Rovner, Sergey Pavlenko, Ivan Glebovich Sokolov and Vladimir Bitkin. See: List of music students by teacher: R to S#Nikolai Sidelnikov.
His works include operas:
- Alen'kiy Tsvetochek (The Scarlet Flower, after S. Aksakov, 1974)
- Chertogon (opera dilogy after Nikolai Leskov: Zagul, Pokhmelye, 1978–1981)
- Beg (The Run after Mikhail Bulgakov, 1987)
- Stepan Razin
and also: 6 symphonies, an oratorio, cantatas, choral, chamber and vocal music.
- Russkie skazki (Русские сказки — The Russian Fairy Tales, 1968) - a concert for 12 players is one of his most notable compositions.