Dobell was born in Cooks Hill, a working-class neighbourhood of Newcastle, New South Wales in Australia to Robert Way Dobell and Margaret Emma (née Wrightson).
His father was a builder and there were six children.

Dobell's artistic talents were evident early.
In 1916, he was apprenticed to Newcastle architect, Wallace L. Porter and in 1924 he moved to Sydney as a draftsman.
In 1925, he enrolled in evening art classes at the Sydney Art School (which later became the Julian Ashton Art School), with Henry Gibbons as his teacher.
He was influenced by George Washington Lambert.
He was also gay and consequently never married, while several of his works carried strong homoerotic overtones.

In 1929, Dobell was awarded the Society of Artists' Travelling Scholarship and travelled to England to the Slade School of Fine Art where he studied under Philip Wilson Steer and Henry Tonks.
In 1930, he won first prize for figure painting at Slade and also travelled to Poland.
In 1931 he moved on to Belgium and Paris, and after 10 years in Europe returned to Australia – taking with him a new Expressionist style of painting as opposed to his earlier naturalistic approach.

In 1939, he began as a part-time teacher at East Sydney Technical College.
After the outbreak of war, he was drafted into the Civil Construction Corps of the Allied Works Council in 1941 as a camouflage painter; he later became an unofficial war artist.

In 1944, he had his first solo exhibition including public collection loans at the inauguration of the David Jones Art Gallery, Sydney.

In 1949, he visited New Guinea as a guest of Sir Edward Hallstrom with writers Frank Clune and Colin Simpson.
The trip inspired a new series of tiny, brilliantly coloured landscapes.
In 1950, he revisited New Guinea; on his return to Australia he continued to paint scenes of New Guinea, as well as portraits.

Between 1960 and 1963 TIME magazine commissioned Dobell to paint four portraits for covers, one per year, of: Sir Robert Menzies, Prime Minister of Australia; South Vietnam's President Ngô Đình Diệm; Frederick G. Donner, the Chairman of General Motors; and Tunku Abdul Rahman, Prime Minister of Malaysia.

In 1964, Dobell exhibited in a major retrospective at the Art Gallery of New South Wales and the first monograph of his work was written by James Gleeson.
Dobell was born in Cooks Hill, a working-class neighbourhood of Newcastle, New South Wales in Australia to Robert Way Dobell and Margaret Emma (née Wrightson). His father was a builder and there were six children.
Dobell's artistic talents were evident early. In 1916, he was apprenticed to Newcastle architect, Wallace L. Porter and in 1924 he moved to Sydney as a draftsman. In 1925, he enrolled in evening art classes at the Sydney Art School (which later became the Julian Ashton Art School), with Henry Gibbons as his teacher. He was influenced by George Washington Lambert. He was also gay and consequently never married, while several of his works carried strong homoerotic overtones.
In 1929, Dobell was awarded the Society of Artists' Travelling Scholarship and travelled to England to the Slade School of Fine Art where he studied under Philip Wilson Steer and Henry Tonks. In 1930, he won first prize for figure painting at Slade and also travelled to Poland. In 1931 he moved on to Belgium and Paris, and after 10 years in Europe returned to Australia – taking with him a new Expressionist style of painting as opposed to his earlier naturalistic approach.
In 1939, he began as a part-time teacher at East Sydney Technical College. After the outbreak of war, he was drafted into the Civil Construction Corps of the Allied Works Council in 1941 as a camouflage painter; he later became an unofficial war artist.
In 1944, he had his first solo exhibition including public collection loans at the inauguration of the David Jones Art Gallery, Sydney.
In 1949, he visited New Guinea as a guest of Sir Edward Hallstrom with writers Frank Clune and Colin Simpson. The trip inspired a new series of tiny, brilliantly coloured landscapes. In 1950, he revisited New Guinea; on his return to Australia he continued to paint scenes of New Guinea, as well as portraits.
Between 1960 and 1963 TIME magazine commissioned Dobell to paint four portraits for covers, one per year, of: Sir Robert Menzies, Prime Minister of Australia; South Vietnam's President Ngô Đình Diệm; Frederick G. Donner, the Chairman of General Motors; and Tunku Abdul Rahman, Prime Minister of Malaysia.
In 1964, Dobell exhibited in a major retrospective at the Art Gallery of New South Wales and the first monograph of his work was written by James Gleeson.
William Dobell