Peter Dickinson was born in 1927 in Zambia and moved to England in 1936. He attended Eton College in 1941 and remained until 1946. After completing his National Service (1946–48), he studied at King's College, Cambridge, graduating with a Bachelor of Arts degree in 1951. For seventeen years, he worked as assistant editor, resident poet and reviewer for Punch magazine.

Dickinson's first two books, The Weathermonger and Skin Deep, were published in 1968. On completing sequels to both debut novels, Dickinson left Punch to be a full-time author the next year. He continued to write poetry for entertainment and occasionally on commission.
Dickinson published almost fifty books including crime fiction for adults, speculative and supernatural fiction for older children, and simpler children's books. One of his few non-fiction books was the collection Chance, Luck and Destiny (1975) won the second annual Boston Globe–Horn Book Award for children's non-fiction in 1977. The Weathermonger became the "Changes" trilogy comprises alongside the books Heartsease and The Devil's Children (1968 to 1970). It was adapted in 1975 as a BBC TV series, The Changes.

Dickinson won the Crime Writers' Association's Gold Dagger award for Skin Deep in 1968 and A Pride of Heroes in 1969. He won the 1977 Guardian Children's Fiction Prize for The Blue Hawk, and both the Whitbread Children's Book Award and the Carnegie Medal for Tulku (1979). He won the Carnegie Medal again the following year for City of Gold. In 1982, Dickinson was named in the International Board of Books for Young People Honor List for Tulku, and The Iron Lion was selected one of New York Times Notable Books. Dickinson was the British nominee in 1988 for the biennial Hans Christian Andersen Award, and one of five finalists for the award in 2000. Eva (1988) was a runner-up for both the Carnegie and the Horn Book Award. Dickinson won the Phoenix Award from the Children's Literature Association for The Seventh Raven (1981) and again in 2008 for Eva (1988). The Kin (1998) made the Whitbread Award shortlist.
Dickinson was elected a Fellow of the Royal Society of Literature in 1999 and appointed an Officer of the Order of the British Empire (OBE) in the 2009 Birthday Honours. He was also chair of the Society of Authors.

Peter Dickinson died on 16 December 2015, his 88th birthday.