Kitty Kielland was born in Stavanger, Norway, and grew up in a wealthy and cultured family. She became interested in painting and drawing late on, and it was not until she was 30 years old that she travelled abroad to study art. In the years 1873–75, she lived in Karlsruhe in Germany, where she was a student of landscape painter Hans Gude (1825–1903), who trained her in Realism and plein air painting. In the years 1875–78, she lived in Munich, where she became part of a community of Norwegian artists, who had settled in the city. Among others, she met the painters Harriet Backer (1845–1932) and Eilif Peterssen (1852–1928), with whom she formed a lifelong friendship.

In 1879, she travelled to France, and together with Harriet Backer she settled in Paris as one of the first Norwegian artists. She lived here in the years 1879–89 – for most of the period together with Backer, with whom she also shared a studio. Both remained unmarried their whole life and devoted themselves fully to their art. In the 1880s, the Parisian Café de la Régence was a gathering point for Scandinavian artists and intellectuals, and here Kielland met i.a. Michael (1849–1927) and Anna Ancher (1859–1935), and in 1889, Anna Ancher painted a portrait of Kielland, which today can be found at The Art Museums of Skagen (Inv. No. HAf7). In 1888, she had also met Marie Krøyer (1867–1940) in Paris.

It was in Paris that she really made her breakthrough as an artist. In 1879, she exhibited at the Salon for the first time – two landscapes from Jæren in Norway – and until 1883 she was represented at the Salon with both Norwegian and French landscapes. For a short period of time, she studied with the landscape painter Léon Pelouse (1838–1891), which influenced her to further develop her plein air painting and to paint with freer and more vibrating brush strokes.

Although Kitty Kielland also painted interiors, e.g. from the apartment and studio in Paris, she was primarily known as a landscape painter, and she is today considered one of the most significant and first Norwegian female landscape painters. She executed several motifs from her home region of Rogaland in Norway, and she has become particularly known for depicting the nature of the Jæren area, which became one of her favorite motifs.

Kielland was strongly involved in the women's movement in Norway, and she eagerly participated in the contemporary debates about women's rights. In 1884, she was one of the founders of the Norwegian Association for Women's Rights.