She has been involved in music since childhood, growing up in a very musical family. Her mother was a singer and flautist, while her father was a jazz pianist and composer. In the early 1990s, she joined the children's group Tęcza and performed in the popular Polish Television program Tęczowy Music Box.

At eighteen, Sadowska released her debut album titled "Jutro" (Tomorrow). Her next two albums, "Lucky Star" and "Crazy," were produced and recorded in the United States, where Sadowska lived for several years. In 2004, after returning to Poland, she released another album titled "Marysia Sadowska," featuring songs composed based on the poems of Maria Pawlikowska-Jasnorzewska and Julian Tuwim. In 2005, she performed at the Opole Festival, where she performed her song "Tu i teraz" (Here and Now). That same year, she was nominated for the Superjedynki Award in the Female Vocalist of the Year category.

Her next musical work, "Gwiazda dla każdego" (A Star for Everyone), was released in 2007. This was followed by "Demakijaż" (Makeup Removal) in 2009 and "Jazz na ulicach" (Jazz on the Streets), which was released five years later. Her latest album, "Początek nocy" (The Beginning of the Night), was released in 2020, and it was promoted by a single recorded in collaboration with Kayah titled "Kocham Cię" (I Love You).