| John Dempsey | |
| Birth Date: | c. 1848 |
| Death Date: | September 14, 1884 |
| Birth Place: | Ireland |
| Death Place: | San Francisco, California, US |
| Placeofburial: | Greenlawn Memorial Park, Colma, California, U.S. |
| Placeofburial Label: | Place of burial |
| Allegiance: | United States |
| Branch: | United States Navy |
| Rank: | Seaman |
| Awards: | Medal of Honor |
John Dempsey (–1884), was an Irish-born American military officer, who served as a United States Navy sailor and a recipient of the United States military's highest decoration, the Medal of Honor.
Born in 1848 in Ireland, Dempsey immigrated to the United States and joined the U.S. Navy from Massachusetts. By January 23, 1875, he was serving as a seaman on the . On that day, while Kearsarge was at Shanghai, China, he jumped overboard and rescued a shipmate from drowning. For this action, he was awarded the Medal of Honor.
Dempsey's official Medal of Honor citation reads:
On board the U.S.S. Kearsarge at Shanghai, China, 23 January 1875. Displaying gallant conduct, Dempsey jumped overboard from the Kearsarge and rescued from drowning one of the crew of that vessel.He died on September 14, 1884, in San Francisco. He was buried at Greenlawn Memorial Park in Colma, California.[1]