Homer Flint (born Flindt; he went by Flint in his professional capacity) was born in 1888 or 1889 in Albany, Oregon to Henry Flindt and Emily Burkhart.

Flindt attended primary and secondary school in San Jose, California but did not graduate from high school. Early jobs he held included working as a delivery boy for a dry goods store, office boy for an insurance agent, and draftsman at an architectural firm. Flindt remained interested in design and inventing things the rest of his life.

Flindt read a variety of romantic fiction from the late 19th and early 20th centuries by such authors as H.G. Wells, Jules Verne, and M. Rider Haggard. He became interested in writing himself and started with the San Jose Morning Times, later writing a monthly column for a shoemakers' magazine while working as a shoemaker for his brother Charles.

In 1907 Flindt met and began courting Mabel Elisabeth Williams. She'd had scarlet fever as a child and so had reduced hearing in both ears. They married in 1911 and had their first child, Max, in 1915. Daughter Bonnie was born in 1918, and their third child, Vella, was born in 1921.

Flint began writing for the movies in the 1910s. While convalescing in the hospital from emergency surgery for appendicitis, he began writing short stories in the genre of "scientific romance" (science fiction) as well as more straightforward short and serialized fiction for pulp magazines. His stories ranged from taking place on the moon ("The Man in the Moon" and "Out of the Moon") to exploring life after death ("The Greater Miracle") to turning a person into a giant ("The Nth Man"). He is also known for his story "The Planeteer" and his novel The Blind Spot (1921), co-authored with Austin Hall.

Flindt's wife moved with their children to Washington, California in the early 1920s so she could teach and earn additional money to support the family. When making plans to reunite permanently, Homer Eon Flindt was killed in a car wreck in March 1924 under mysterious circumstances.