Medary.com

Killed by a sniper while emerging from a courthouse.  He was 66.
Yahoo News:

According to the comic, the superhero was spawned when a scrawny arts student named Steve Rogers, ineligible for the army because of his poor health but eager to serve his country, agreed to a "Super Soldier Serum" injection. The substance made him a paragon of physical perfection, armed only with his shield, his strength, his smarts and a command of martial arts.

In the comic-book universe, death is not always final. But even if Captain America turns out to have met his end in print, he may not disappear entirely: Marvel has said it is developing a Captain America movie.