Alexander Abramovich Krein (Aleksandr Abramovich Kreyn; 20 October 1883 in Nizhny Novgorod – 25 April 1951 in Staraya Ruza, Moscow Oblast) was a Russian/ Soviet composer.

Fragment lyrique, Op. 1a (1903)
Dedication: Vladimir Limarev

Cello Quartet
Aron Zelkowicz, David Premo, Michael Lipman, Mikhail Istomin

In 1896, at the early age of 14, Alexander Krein entered the Moscow Conservatory where his studies included cello classes with Alexander von Glehn and composition lessons with Sergei Taneyev and Boleslav Yavorsky. His first works were published by P. Jurgenson in 1901. During the years immediately prior to the 1917 Revolution, he was on the faculty of the People's Conservatory in Moscow. In 1917, he was appointed as director of the artistic wing of the Muzo-Narkompros, the music section of a newly formed ministry of arts and education. Throughout the 1920s, Krein was widely regarded as the leader of a Jewish national school in Russia (which included his brother Grigori and his nephew Julian). Among those he influenced were minor composers such as Sinovii Feldman. After the formation of the Soviet Union, he held a variety of official and semi-official music administration posts. He died April 1951 in Staraya Ruza. His son, Alexander Kron, was a Soviet playwright.