Alexej Alexieff graduated from the Academy of Music and Dance Art in Plovdiv majoring in Piano under Professor Todor Kiuvliev, Choral Conducting under Professor Dimitar Ruskov, Music Forms and Orchestration under Professor Bojidar Abraschev. He also studied Composition under Ivan Dimov, Professor Ivan Spassov and Professor Bojidar Abraschev. After he graduated, he continued to study Composition at the State Academy of Music under Professor Parashkev Hadjiev and Professor Tzvetan Tzvetanov. He studied simultaneously under Professor Alexander Raychev, Professor Alexander Tanev and Professor Vassil Kazandjiev. He completed his studies in 1976. In 1974 he took part in concerts carried out by the Union of Bulgarian Composers. In 1985 he played piano works written by colleagues of his. He worked actively with non-professional choir ensembles such as the Sofia Youth Male Voices Choir, the Saint Sofia Choir (the former Spontaneous Song Mixed Choir), the male voices choir Slavia, the Mixed Choir of the Transport Workers, the Female Voices Choir at the Emergency Institute “Pirogov”. He also worked with the professional mixed choir at the Union of Blind People “Academician Petko Staynov” (1986-99). Since 1997 he has written mainly church music.

He composed choral works; a symphony; solo songs; vocal cycles; piano works, etc. The mixed choir Academician Petko Staynov conducted by Petar Matev has performed works of his.

For choir and orchestra:

Christmas Carol “Ode for children’s choir, symphony orchestra and organ” (1996).

Ballad to the Nine for mixed choir, string and percussion, after Eftim Eftimov.

For symphony orchestra:

Symphony N1 “Bulgaria Old and Young” (1975-1980)

For string orchestra:

Metamorphoses (1975).

Chamber music:

Sonatina for flute and piano (1975);
Images cycle of four pieces for flute and piano (1975);
Portrait of a Roman Matron for violin and piano (1978).

Solo songs and vocal cycles:
Ave Amor (1978);
Four Shakespeares Sonnets for soprano, mezzo-soprano and piano (1979).

Choral works:

For mixed choir:
Les Proverbes de Fenis after French Medieval Maxims;
Guslarska balada (Gusla Players Ballad) after lyrics by Stefan Stanchev.

For mixed choir and piano:

Thirteen Centuries.

For soloists and male voices choir:

Two Poems after Nikolay Liliev.

 Church music for mixed choir:

Divine Liturgy after St. John Chrysostom;
Holy God;
Molitvami Bogoroditzi (1997);
Antiphon to Christmas (1998);
Dostoyno Est (1999).