life story vs life history

life story and life history both are nouns.

Word	Noun	Adjective	Verb	Adverb
life story	Yes	No	No	No
life history	Yes	No	No	No

As nouns, life story and life history are synonyms defined as:

life story and life history: an account of the series of events making up a person's life

Other synonyms of life story include biography, life.

life story (noun)	life history (noun)
an account of the series of events making up a person's life	the general progression of your working or professional life
	an account of the series of events making up a person's life