Yasen Gyuzelev was born in Sofia. His father is the famous Bulgarian opera singer Nikola Guselev, and Yasen's brother is the artist Chavdar Guselev.
Yasen Gyuzelev graduated from the National Academy of Arts and then went to work in Italy. He illustrated a series of books, including "Alice in Wonderland" and "Alice Through the Looking Glass" by Lewis Carroll, "Pinocchio" by Carlo Collodi, "Don Quixote" by Cervantes, "Oliver Twist" by Charles Dickens, stories about the life of personalities like Socrates and Michelangelo, and many others.
Guselev was named Illustrator of the Year at the Bologna International Book Fair in 1994. With his illustrations in "Alice in Wonderland" he gained worldwide fame among illustrators. He won the "Konstantin Konstantinov" award for illustrator in 2011. Guzelev also illustrated a deluxe edition of The Hound of the Baskervilles and many other books.