Together with her sister Izabela, Olga Boznanska received her first lessons in drawing from her mother. Her subsequent teachers were Jozef Siedlicki, and Kazimierz Pochwalski. She then studied painting with Hipolit Lipinski and from 1884 to 1886 attended the courses of A. Baraniecki in Krakow. Further studies were undertaken in Munich, initially in private school run by Karl Kichendorf and later under the tutelage of the modernist Wilhelm Durr. Other Polish artists in Munich at that time, such as Jozef brandt , Alfred Wierusz-Kowalski, and Waclaw Szymanowski, also took and interest in her development.
After three year study in Munich Boznanska opened her own studio there. She Befriended a number of Munich painters, among them Paul Nauen, whose portrait by her hangs in the National Museruum in Warsaw. She remained in Munich until 1898, traveling occasionally to France, Switzerland, Vienna and Berlin.
In 1895 the Berlin journal Bazaar included Boznanska among the twelve women painters in Europe. That same year she succeeded Theoedor Hummel in his private school of painting in Munich, where she was highly regarded for her teaching. She was subsequently offered – but declined – the directorship of the women`s section of the women`s section of the Academy of Fine Arts in Krakow. Boznanska debuted in Paris in 1896, at the salon of the Societe nationale de beaux-arts. In 1904 she became a member of the society. In 1898 she moved permanently to Paris. Boznanska belonged to the "Sztuka" Society of Polish Artists, the Association of Polish Women Artist in Krakow, the International Society of Sculptors, Engravers and Painters, the Society of Polish Artists in Paris, and the Polish-Artistic Society.
Boznanska began to exhibit early, both in Poland and elsewhere, and she participated in a number of international exhibitions. In her lifetime, however, she had only a single woman show in Poland, at the Krakow Society of the Friends of Art in 1931. Posthumous exhibitions were held at the Bibliotheque polonaise in Paris in 1945 and the Society of Fine Arts in Krakow the fallowing year. A comprehensive retrospective exhibition was mounted at the National Museum in Krakow in 1960.
Boznanska was the recipient of numerous artistic awards, including that of the Probusz Barczewski Foundation in 1908 and the Award for the City of Warsaw in 1934. She was honored with the French Legion of Honor in 1912 and the Order of Polonia Restitutta in 1938. In 1859 a plaque honoring her was placed at the site of Academie Colarossi in Paris (16 rue de la Grande Chaumiere), where Boznanska had taught drawing. The artist is buried in the Polish cemetery of Monmercy near Paris.
Notwithstanding her popularity as a teacher and her wide success as an artist Boznanska led and unusually modest and solitary life in Paris. In her final years she confined herself almost entirely to her studio.
Boznanska is esteemed primarily as a portraitist and secondarily as a painter of still lifes and landscapes. Although her work reveals the influence of James A. Whistler – particularly in the slivery coloring and the sketchy contours – and that of certain French postimpressionists, Boznanska developed an individual style. In her portraits she concentrated on capturing the psychology of the subject, but not by bringing him or her closer to the viewer in a realistic manner (for example, through a sharper modeling of the features). Instead, her effects were achieved through a subtle sinking of the silhouette or head into a background of similar tone. Muted hues, primarily cool, diaphanous greenish planes, a matte surface (usually cardboard without a ground) and a light brush stroke create the impression of a delicate screen suspended between the subject and the viewer. The effect does not detract from a sharp, expressive characterization of the face.
Boznanska works can be found in museums in Poland (especially in the national museums in Krakow and Warsaw) as well as in Paris, Venice, and Prague, and in Polish and foreign private collections.