Jan Nigro, painted in various media, abstracts and human figures, though she is best known for her colourful nude figures.She exhibited her art at the Auckland City Art Gallery in 1939, and again the following year, as a member of the Auckland Society for Arts. In 1946 she participated in a show in Sydney. Her first solo show was in Melbourne in 1948,with a second in the same city in 1950, and another upon returning to live in New Zealand in 1952. Further solo and group shows followed, with multiple exhibitions nearly every year from the mid-1960s until her death.
In 2016 a posthumous solo exhibition of Nigro's work was mounted at the Aesthete Gallery in Hamilton New Zealand. Her work is held in the collections of Auckland Art Gallery, Toi o Tāmaki, Te Papa and Waiheke Community Art Gallery.