Penelope Seidler

The Seidlers' home in Killara, New South Wales

Penelope Alice Marjorie Seidler AM (née Evatt; born 1938) is an Australian architect and accountant. She is director of the Sydney-based architectural firm Harry Seidler and Associates. She was the wife and professional partner of architect Harry Seidler (1923–2006). Together they designed "Harry & Penelope Seidler House", which won the Wilkinson Award in 1967.

She has long been a patron of the arts, and as of April 2024 she is a member of the National Gallery of Australia Foundation Board.