Thomas Byrne Dunn (March 16, 1853 in Providence, Rhode Island – July 2, 1924 in Rochester, Monroe County, New York) was an American businessman and politician.

He founded and was President of the T. B. Dunn Company which manufactured perfumes and extracts.

He was an alternate delegate to the 1920 Republican National Convention.

He was interred in a family mausoleum in Mount Hope Cemetery, Rochester.

The Tiffany window from the mausoleum is on display at the Memorial Art Gallery, Rochester.