From 1937 till 1941 Yaroslav was studied at СХШ. His teachers were Konstantyn Lepilov, Olga Bogaevskaya, Mikhail Natarevich. When thу War was beginning Yaroslav with his family evacuated from Leningrad to Rostov the Great. After returning he entered to the painting department of the ЛВХПУ. In the autumn of 1945 a tragic event was happened with him: he lost an eye during a hunt. To save a colour sensing he had to change the painting department to the restoration one, which he graduated at 1948.
From 1948 till 1950 he worked as an artist-restorer of the wall-painting at the State restoration workshop.
Meanwile he began to attend the courses at the Ilya Repin Institute as an extern and in 1950 he entered to the Graphic Department of it. After 2 years he changed the Department into the Painting and in 1956 he graduated from Ilya Repin Institute in Mikhail Bobyshov workshop. His Diploma work were series of sketches to the scenery and costumes of an Nikolai Rimsky-Korsakov`s opera \"Snegurochka\".
Since 1957 Yaroslav Krestovsky has participated in Art Exhibitions. He painted cityscapes, portraits, still lifes, and genre paintings. Yaroslav Krestovsky was a member of Saint Petersburg Union of Artists (before 1992 Leningrad branch of Union of Artists of Russian Federation) since 1958.
At 1960s Yaroslav Krestovsky was a Teacher of the Painting Department of ЛВХПУ.
He painted cityscapes and landscapes, still lifes, portraits, genre compositions. His manner especially took the form at the end of 1950s till the middle of 1970s.
Yaroslav Krestovsky was aт a particypant of the Groupe \"Eleven\". The Exhibition of Eleven (Leningrad, 1972) artists (called later as the exhibition of \"Eleven\") was opened October 24th, 1972 in Okhta Exhibition Hall of the Union of Artists of the Russian Federation [25]. Another members of the Group were: artists Valery Vatenin, German Yegoshin, Zaven Arshakuny, Boris Shamanov, Leonid Tkachenko, husband and wife Victor Teterin and Evgenia Antipova, Valentina Rakhina, a wife of German Yegoshin, Vitaly Tulenev and sculptor Konstantin Simun with support of art-critic Lev Mochalov. It showed the creation of the \"left wing\" of the Leningrad Union of Soviet Artists in concentration. The second exhibition was in 1976 at the same place and just 9 artists of 11 took part in it. In the future they demonstrated their art works in solo or in the big common exhibitions with two or tree participants in Moscow and Leningrad. In 1990 the members of \"Eleven\" engaged in the common exhibition of 26 Leningrad and Moscow artists in Central Exhibition Hall \"Manezh\" in Saint-Petersburg.
In 1970s the eyesight of Krestovsky suddenly began to fall, he couldn`t paint from this time and late went blind. His last works dates by 1977.
His personal Exhibitions were in Leningrad (1983), Moscow (1986), Saint Petersburg (1995, 2000).
Paintings by Yaroslav Krestovsky are in State Russian Museum, State Tretyakov Gallery, in Art museums and private collections in Russia, USA, Japan, China, and throughout the world.