Dennisville is an unincorporated community and census-designated place (CDP)[5] located within Dennis Township, in Cape May County, in the U.S. state of New Jersey.

The main transportation artery is New Jersey Route 47 (Delsea Drive).

[7] The first post office in the area was Dennis Creek, established September 7, 1802, with Jeremiah Johnson as first postmaster.

[8] In the 1880s, a local industry sprung up—described by The New York Times as "the like of which does not exist anywhere else in the world"—in which cedar trees that had fallen as much as decades earlier were recovered from under the surface of local swamps.

The trees, ranging in size from 4 to 6 feet (1.2 to 1.8 m) in diameter, were first discovered in 1812 and became the foundation of a thriving economic boom in the area for shingles and staves.