[4] Harrison's musical training is reflected in her poetry: "she was adept in her handling of the rhythmic complexities of poetic forms such as the sonnet and the villanelle.

Like other Canadian poets of the late nineteenth century, her prevailing themes include nature, love, and patriotism.

Her landscape poetry, richly influenced by the works of Charles G.D. Roberts and Archibald Lampman, paints the Canadian wilderness as beguilingly beautiful yet at the same time mysterious and distant.

Her two novels "articulate a fascination with a heavily mythologized Quebec culture that Harrison shared with many English-speaking Canadians of her time ... characterized by a gothic emphasis on horror, madness, aristocratic seigneurial manor houses, and a decadent Catholicism.

"[6] "Harrison writes elegiacally of a regime whose romantic qualities are largely the creation of an Upper Canadian quest for a distinctive historical identity.

In 1916 anthologist John Garvin called her "one of our greater poets whose work has not yet had the recognition in Canada it merits.".

"[7] The Dictionary of Literary Biography wrote of Susan Frances Harrison, in 1990,[7] that "Harrison's unpublished work has not been preserved, her published work is out of print and difficult to obtain, and her once-substantial position in the literary life of her country is now all but forgotten.