He studied composition at the St. Petersburg Conservatory, where he was a student of Rimsky-Korsakov. After graduation in 1882 he became a professor at the Moscow Conservatory. There both Scriabin and Rachmaninoff were his students. In 1895 Arensky returned to St. Peterburg as director of the Imperial Choir. He retired in 1901, spending his time as a pianist, conductor, and composer.
Arensky died of tuberculosis in 1906. It is alleged that drinking and gambling helped undermine his health.
Tchaikovsky was the greatest influence on Areksy's musical compositions. Indeed Rimsky-Korsakov said, 'In his youth Arensky did not escape some influence from me; later the influence came from Tchaikovsky. He will quickly be forgotten.' While it is true that Arensky is not as well-remembered as some of his contemporaries, his music is still occasionally played and recorded.