Joan Eardley was born in Warham, Sussex in 1921. She studied at Goldsmith's School of Art, London and later, when her family moved to Glasgow, at the Glasgow School of Art (1940-1943) under Hugh Adam Crawford. After three years spent working as a joiner's labourer, she spent the summer of 1947 studying under James Cowie at the Patrick Allen-Fraser School of Art, Hospitalfield. In 1948-1949 she was awarded travelling Scholarships by the Royal Scottish Academy and Glasgow School of Art which took her to France and Italy. The resulting work was shown at her first solo exhibition at Glasgow School of Art. On her return she set up studio in an old tenement in Glasgow and for the next few years painted the colourful street life of the local young children and the scullery interiors.
In 1951 she was introduced to the remote fishing village of Catterline on the North East Coast of Scotland. For the next decade she divided her time between Glasgow and Catterline, eventually acquiring a house and studio there. In Catterline it was the sea and land that were the inspiration for her paintings - the wild, windswept coastline and the fields and hedgerows above the cliffs. She painted throughout the different seasons, often outdoors, and in various weathers. The freely painted, often bleak and desolate works that resulted are among the most powerful and individual landscapes in 20th century British art.
Eardley's work was highly acclaimed by the time of her early death in 1963 at the age of just 42.
Her work can be found in the National Galleries of Scotland as well as many other galleries across the world. She became a member of the Royal Scottish Academy in 1963, just before her death.