Despite his status as a commoner, Borodin was well provided for by his Georgian Father and grew up in a large four-storey house, which was gifted to Alexander and his "aunt" by the nobleman. Although his registration prevented enrollment in a proper gymnasium, Borodin received good education in all of the subjects through private tutors at home. In 1850 he entered the Medical–Surgical Academy in Saint Petersburg, which was later home to Ivan Pavlov, and pursued a career in chemistry. On graduation he spent a year as surgeon in a military hospital, followed by three years of advanced scientific study in western Europe.

No other member of the Balakirev circle identified himself so openly with absolute music as did Borodin in his two string quartets, and in his many earlier chamber compositions. Himself a Cellist, he was an enthusiastic chamber music player, an interest that deepened during his chemical studies in Heidelberg between 1859 and 1861. This early period yielded, among other chamber works, a string sextet and a piano quintet. In thematic structure and instrumental texture he based his pieces on those of Felix Mendelssohn.

Borodin met Mily Balakirev in 1862. While under Balakirev's tutelage in composition he began his Symphony No. 1 in E-flat major; it was first performed in 1869, with Balakirev conducting. In that same year Borodin started on his Symphony No. 2 in B minor, which was not particularly successful at its premiere in 1877 under Eduard Nápravník, but with some minor re-orchestration received a successful performance in 1879 by the Free Music School under Rimsky-Korsakov's direction. In 1880 he composed the popular symphonic poem In the Steppes of Central Asia. Two years later he began composing a third symphony, but left it unfinished at his death; two movements of it were later completed and orchestrated by Alexander Glazunov.

In 1868 Borodin became distracted from initial work on the second symphony by preoccupation with the opera Prince Igor, which is seen by some to be his most significant work and one of the most important historical Russian operas. It contains the Polovtsian Dances, often performed as a stand-alone concert work forming what is probably Borodin's best-known composition. Borodin left the opera (and a few other works) incomplete at his death.

In 1875 Borodin started his First String Quartet, much to the displeasure of Mussorgsky and Vladimir Stasov. That Borodin did so in the company of The Five, who were hostile to chamber music, speaks to his independence. From the First Quartet on, he displayed mastery in the form. His Second Quartet, in which his strong lyricism is represented in the popular "Nocturne", followed in 1881. The First Quartet is richer in changes of mood. The Second Quartet has a more uniform atmosphere and expression.

Borodin's fame outside the Russian Empire was made possible during his lifetime by Franz Liszt, who arranged a performance of the Symphony No. 1 in Germany in 1880, and by the Comtesse de Mercy-Argenteau in Belgium and France. His music is noted for its strong lyricism and rich harmonies. Along with some influences from Western composers, as a member of The Five his music exudes also an undeniably Russian flavor. His passionate music and unusual harmonies proved to have a lasting influence on the younger French composers Debussy and Ravel (in homage, the latter composed in 1913 a piano piece entitled "À la manière de Borodine").

The evocative characteristics of Borodin's music made possible the adaptation of his compositions in the 1953 musical Kismet, by Robert Wright and George Forrest, notably in the songs "Stranger in Paradise" and "And This Is My Beloved". In 1954, Borodin was posthumously awarded a Tony Award for this show.

Prince Igor was completed posthumously by Rimsky-Korsakov and Glazunov. It is set in the 12th century, when the Russians, led by Prince Igor of Seversk, set out to conquer the barbarous Polovtsians by travelling Eastward across the Steppes. The Polovtsians were apparently a Nomadic tribe originally of Turkish origin who habitually attacked southern Russia. A full solar eclipse early in the first act foreshadows an ominous outcome to the invasion. Prince Igor's troops are defeated. The story tells of the capture of Prince Igor, and his son, Vladimir, of Russia by Polovtsian leader Khan Konchak, who entertains his prisoners lavishly and calls on his slaves to perform the famous 'Polovtsian Dances', which provide a thrilling climax to the second act. The second half of the opera finds Prince Igor returning to his homeland, but rather than finding himself in disgrace, he is welcomed home by the townspeople and by his wife, Yaroslavna. Although for a while rarely performed in its entirety outside of Russia, this opera has received two notable new productions recently, one at the Bolshoi State Opera and Ballet Company in Russia in 2013, and one at the Metropolitan Opera Company of New York City in 2014.