Oleksandr Semchuk began his violin studies at the age of 4 under Maestro I. Pylatiuk. At only 8 years old, he performed his first solo concert with an orchestra, marking the early stages of a remarkable career. His talent was nurtured by some of the world’s most renowned violinists, including Bohodar Kotorovych, Yehudi Menuhin, Tibor Varga, Viktor Tretyakov, and Alberto Lysy.

Early in his career, Oleksandr won numerous international competitions, including the highly prestigious "Youth Assembly of Art" in Moscow, a coveted prize among Soviet musicians, and the "Mykola Lysenko International Competition" in Ukraine. These early achievements set the stage for a flourishing international career, both as a soloist and in chamber music. His collaborations span some of the most distinguished names in the classical music world, such as B.Canino, R.Koelman, V.Sirenko, A.Lucchesini, O.Mandozzi, M.Brunello, V.Kozhukhar, K.Bogino, M.Kugel, V.Mendelssohn, E.Dindo, G.Mirabassi, M.Rysanov, M.Diadiura, O.Kogan, D.Cohen, B.Petrushansky, K.Karabits, N.Eppinger, D.Shapovalov, A.Casellati, L.Passerini, G.De Lorenzo, and many others. He has performed with leading orchestras from across the former Soviet Union and Italy.

In recognition of his cultural contributions, Oleksandr was awarded the title of "Merited Artist of Ukraine" in 2002, following his role as founder and promoter of the "Artists for the Renaissance of Ukraine" project. Notably, he remains the youngest artist across the former Soviet Union to have received the "Title of Honour" from the State. His accolades continued with honours such as the "Laszlo Spezzaferri" prize in 2013 and the "Rinaldo Rossi" prize in 2014, awarded for his contributions to the development of the Italian violin school.

Since 2002, Oleksandr has lived in Italy, where he balances a thriving career as both a performer and an educator. He has held teaching positions at the Fiesole School of Music and the Florence Music Academy, and from 2010 to 2020, he was the head of the String Department at the Imola International Academy "Incontri col Maestro", one of Italy’s most prestigious music institutions. Under his guidance, over 80 of his students have won first prizes at international competitions, including the Oistrakh International Competition (Moscow), Brahms International Competition (Pörtschach), Monaco Master's International Competition, and the Kreisler International Competition (Vienna). His former students now hold principal positions in major orchestras such as London Symphony Orchestra, the “Santa Cecilia” and “La Scala” Symphony Orchestras, Mozart Orchestra, Teatro San Carlo Orchestra of Naples and the Mahler Youth Orchestra, and many have become professors at conservatories and universities across Europe.

Oleksandr’s artistic output is equally distinguished by his numerous recordings, including over seven hours of solo repertoire featured in Ukraine’s "Golden Collection," with landmark works such as the concertos of Brahms, Tchaikovsky, and Sibelius. His contributions to music have also extended to the realm of composition. In 2014, the Ukrainian composer Eugen Stankovych composed and dedicated the trio "Prayer for Peace" to Oleksandr, which had its world premiere in San Marino. In 2020, Maestro Stankovych dedicated a violin concerto-suite to him, which had its first performance in October 2021 with the National Symphony Orchestra of Ukraine, celebrating the 30th anniversary of Ukraine’s independence.

One of the most notable recent moments in his career was his participation in the 2022 concert "AD MEMORIAM", dedicated to the Ukrainian heroes of the 2014 Revolution of Dignity. This concert, sponsored by the Italian Embassy and the Italian Cultural Center, included the world premiere of Stefano Delle Donne’s "Piccola Suite Celeste", dedicated to the victims of the Heavenly Hundred. In 2023, Oleksandr opened the 10th edition of the Stradivari Festival in Cremona, performing a piece written and dedicated to him, alongside the orchestra "I Filarmonici di Roma" and violinist Ksenia Milas.

Beyond his performing career, Oleksandr remains deeply involved in charitable and cultural projects. His work on the project "Music Unites", aimed at raising funds for the #EmergenzaUcraina initiative, earned him the "International Good Practices Award" from News ReMind and the European Parliament’s Italian Office. He and his wife, Ksenia Milas, also received the "Excellence Award" from theAssociation “Evento Donna” for their artistic and humanitarian efforts.

Oleksandr frequently holds masterclasses at institutions such as the Royal College of Music (London), the Paris Conservatory, and numerous Italian state conservatories. He is often invited to serve on juries for international competitions, collaborating with esteemed colleagues like Ivry Gitlis, Krzysztof Wegrzyn, Ilya Grubert, Pierre Amoyal, Francesca Dego, Massimo Quarta, Vladimir Ashkenazy, Miguel Da Silva, and others.

He plays an Auguste Bernardel violin from 1840, using a bow named “Lady Bianca” made by Daniele Navea–Vera (Cremona) for Maestro.