Raija Siekkinen graduated in humanities and lived in Kotka. She worked at a library, as a researcher for an open-air museum, and as a critic, but from 1984 until her death, she made her living from her writing.
She was known first and foremost as a novelist. In crystal clear language, she describes loneliness and alienation. Plot played a subordinate role in her psychological portraits of people. After her debut short story collection Talven tulo, 1978, she published Tuomitut, 1982, Eläman keskipiste, 1983, Pieni valhe, 1986, Kuinka rakkaus syntyy, 1991, Metallin maku, 1992, and Kaunis nimi, 1996.
In 1988, she made her debut as a novelist with Saari, and in 1994 her novel Häriö maisemassa was published. Raija Siekkinen also wrote children's books, including Herra Kuningas, 1986.