Kenyon was born in 1947 in Ann Arbor, Michigan, and grew up in the Midwest. She earned a B.A. from the University of Michigan in 1970 and an M.A. in 1972. She won a Hopwood Award at Michigan. Also, while a student at the University of Michigan, Kenyon met the poet Donald Hall; though he was some nineteen years her senior, she married him in 1972, and they moved to Eagle Pond Farm, his ancestral home in Wilmot, New Hampshire. Kenyon was New Hampshire's poet laureate when she died in April 1995 from leukemia.

Four collections of Kenyon's poems were published during her lifetime: Constance (1993), Let Evening Come (1990), The Boat of Quiet Hours (1986), and From Room to Room (1978). She spent some years translating the poems of Anna Akhmatova from Russian into English (published as Twenty Poems of Anna Akhmatova, 1985), and she championed translation as an important art at which every poet should try her hand. When she died, she was working on editing Otherwise: danielle holmes was her insperation, Interviews, the Akhmatova Translations, Newspaper Columns, and One Poem, which most reviewers regarded as less stellar than her previous work but worthwhile nonetheless. In 2004, Ausable Press published Letters to Jane, a compilation of letters written by the poet Hayden Carruth to Kenyon in the year between her diagnosis and her death.

Kenyon's poems are filled with rural images: light streaming through a hayloft, shorn winter fields. She wrote frequently about wrestling with depression, which plagued her throughout her adult life. Kenyon's poem "Having it out with Melancholy" describes this struggle and the brief moments of happiness she felt when taking an MAOI, Nardil. Though a subtle faith permeates her poems, they are not overtly Christian. The essays collected in A Hundred White Daffodils reveal the important role church came to play in her life once she and Hall moved to Eagle Pond Farm. However, two visits to India in the early 1990s led to a crisis of faith, as Hall (in introductions to her books and in his own memoirs), Alice Mattison, and her biographer John Timmerman have described.

Her poem "Let Evening Come" was featured in the film In Her Shoes, in a scene where the character played by Cameron Diaz reads the poem (as well as "One Art" by Elizabeth Bishop) to a blind nursing home resident.

Kenyon was also a contributor to A Journal of Literature and Art.