Robert Thornby (27 Maart 1888 – 6 Maart 1953) was 'n Amerikaanse regisseur, akteur, en skrywer. Hy was bekend vir sy rolle in die rolprente The Fair Barbarian (1917), Her Inspiration (1918), The Drivin' Fool (1923), en West of Broadway (1926).
- 1916: The Almighty Dollar
- 1916: The Crucial Test
- 1916: The New South
- 1916: Her Maternal Right
- 1916: A Woman's Power
- 1917: The Fair Barbarian
- 1917: Forbidden Paths
- 1917: The Hostage
- 1917: Little Miss Optimist
- 1917: On Dangerous Ground
- 1917: A Kiss for Susie
- 1917: Molly Entangled
- 1918: Her Inspiration
- 1918: Fallen Angel
- 1918: Lawless Love
- 1918: A Little Sister of Everybody
- 1919: Carolyn of the Corners
- 1919: Fighting Cressy
- 1919: The Prince and Betty
- 1919: When My Ship Comes In
- 1919: Are You Legally Married?
- 1919: Rose o' the River
- 1920: The Deadlier Sex
- 1920: Felix O'Day
- 1920: The Girl in the Web
- 1920: Simple Souls
- 1920: Half a Chance
- 1921: The Blazing Trail
- 1921: The Fox
- 1921: Magnificent Brute
- 1921: That Girl Montana
- 1922: The Kickback
- 1922: The Sagebrush Trail
- 1922: The Trap
- 1923: The Drivin' Fool
- 1923: Gold Madness
- 1923: Stormswept
- 1926: West of Broadway
- 1926: The Speeding Venus
