His mother was the daughter of Dutch politician Samuel van Houten, and his younger brother was Scottish economist Sir Frederick Leith-Ross.

[4] He studied in New York City at the National Academy of Design School under Charles Yardley Turner, beginning in 1910.

They were famous for spending afternoons sketching on the bridge at New Hope (and for tossing anything that displeased them into the Delaware River).

[9] Leith-Ross exhibited oil and watercolor paintings at the National Academy of Design in the 1910s,[3] and at the Art Institute of Chicago in the 1920s.

[4] He exhibited at the Pennsylvania Academy of the Fine Arts most years from 1916 to 1952,[10] and won prizes from the Salmagundi Club and the American Watercolor Society.

[3] Leith-Ross was elected an Associate of the National Academy of Design in 1928, and Folinsbee painted his diploma portrait.

[12] Leith-Ross expressed his philosophy about painting in The Landscape Painter's Manual (1956), Watson Guptill Publications.

[3] The Michener Museum hosted a posthumous exhibition of his works, Poetry in Design: The Art of Harry Leith-Ross (October 2006 - March 2007).