Theology and Sermons:
* The Monk and the Knight: A historical novel based on the life of Francis of Assisi.
* The Man Who Dared to Be True: A biographical sketch of Martin Luther.
* The Gospel of the Higher Life: A collection of sermons.
* Christianity and Social Progress: A series of lectures on the social implications of Christianity.
* The New Life: A devotional work on Christian living.
* The Christ of Today: A book examining the relevance of Jesus Christ in modern times.
Historical and Biographical Works:
* The Life of William McKinley: A biography of the 25th President of the United States.
* The Story of America for Young People: A children's history book.
* The American Spirit: A collection of essays on American history and culture.
* The History of the Armour Institute of Technology: A record of the early years of the institute, which Gunsaulus founded.
Other Writings:
* The Higher Life: A collection of poems.
* The Heart of the World: A collection of essays on art, literature, and philosophy.
* The Beautiful in Nature and Art: A work on aesthetics.
* The Message of the Bird: A book on ornithology.
Gunsaulus was a gifted writer and speaker, known for his eloquent prose, his profound religious insights, and his passionate commitment to social justice. His works continue to be read and appreciated today.