The delegation includes US Reps Emanuel Cleaver of Missouri, Sam Farr and Barbara Lee of California and Gregory Meeks of New York.
Cleaver says they are hoping to start negotiations on securing the release of Alan Gross, a Maryland native.
Lee says it is time for both countries to "make a serious commitment" to serious negotiations.
The delegation also met yesterday with Cuban Foreign Minister Bruno Rodriguez.
Gross was arrested in 2009 after he was caught setting up hard-to-detect Internet networks for Cuba's small Jewish community on a US government contract. Havana considers such programs to be an affront to its sovereignty.