Kelley Armstrong was born on 14 December 1968 in rural Sudbury, Ontario, Canada.
She is the oldest of four children of Oral and Marshall Armstrong, in a "typical middle class family" in London, Ontario. Since 12 May 1990, she is married with Jeffrey Fricke, and they had three children; Julia, Alexander, and Marcus, the family continued living in rural Ontario. ter graduating with a degree in psychology from The University of Western Ontario, Armstrong then switched to studying computer programming at Fanshawe College so she would have time to write.

She is best known for the Women of the Otherworld series, since her first novel “Bitten” was released in 2001. She wrote from the security of her dungeon in the basement, where she creates tales of ghosts, demons and werewolves. Her fiction mixes supernatural characters existing in the modern world, strong romantic elements and a mystery plot.