Andrea Lassakova was born in Dolny Kubin, Slovakia, and received her dance training exclusively with Klara Skodova at the Eva Jacz Dance Conservatory in Bratislava, the primary training facility for the Slovak National Ballet. She graduated from the Conservatory in 2011, and the same year joined the Slovak National Theatre as a demi-soloist, where she performed roles in ballets including The Nutcracker, Sleeping Beauty, Le Corsaire, La Sylphide, the Swan Lake, Giselle and The Little Prince.

In 2013-2014, Andrea moved to Finland and became a dancer of the Youth Company of the Finnish National Ballet. In 2014-2015, she joined the Finnish National Ballet’s Main Company. In 2015, Andrea moved to St. Petersburg, Russia, and joined the Mikhailovsky Ballet by invitation as soloist, and was promoted to the rank of First Soloist in 2021, dancing major principal repertoire including Odette/Odile in the Swan Lake, Medora in Le Corsaire, Gamzatti in La Bayadere, Lilac Fairy in Sleeping Beauty, Queen of the Dryads in Don Quixote, Queen of Willis in Giselle, Fairy of the Summer in Cinderella and Sylvia variation from Coppélia by Messerer.

Andrea was one of the few ballerinas to work under the tutelage of Madame Tatiana Nikolaevna Legat. From 2021-22 she was coached by former Kirov Ballet Prima Ballerina Zhanna Ayupova and worked frequently with choreographers Nacho Duato, Oleg Vinogradov, and Mikhail Messerer.