USS Henry Janes was a mortar schooner acquired by the United States Navy during the American Civil War.

Henry Janes was purchased by the Union Navy from her owners, Van Brunt and Slaght, at New York City 27 September 1861.

With the flotilla formed by the end of February, it sailed to join the West Gulf Blockading Squadron for the Mississippi River operations specifically aimed at the capture of New Orleans, Louisiana.

The ships remained off Vicksburg in July and Henry Janes bombarded the city's defenses on the 15th, before proceeding downriver, engaging shore batteries as she went.

Henry Janes returned to blockading duties, with occasional boat expeditions into the innumerable passes and inlets of the Texas coast.