Mary Barber may refer to:

• Mary Barber (poet) (c. 1685 – c. 1755), Irish poet
• Mary Elizabeth Barber (1818–1899), British-born naturalist
• Mary Barber (bacteriologist) (1911–1965), British pathologist and bacteriologist
• Mary Augustine Barber (1789–1860), American educator and Visitation sister

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