Thomas Dyer may refer to:

• Thomas Dyer (1856–1857), mayor of Chicago, Illinois.
• Thomas Dyer (MP) for Bridgwater (UK Parliament constituency)
• T. F. Thiselton-Dyer (Thomas Firminger Thiselton-Dyer, 1848–1923), English writer of popular non-fiction books
• Thomas Henry Dyer (1804–1888), English historical and antiquarian writer

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