The Computer History Museum in Mountain View, Calif., confirmed the death of Engelbart, who died at his home in Atherton, Calif., Tuesday.
His wife, Karen O'Leary Engelbart, said Engelbart, 88, died of kidney failure, The Washington Post reported.
In the early days of computers when machines took up entire rooms and ran programs off of punch cards, Engelbart led a team of researchers determined to make computers easier to use and friendlier, turning them into a staple of work and home life.
In 2000, he received the National Medal of Technology, the nation's highest award in that field. "More than any other person," the citation read, "he created the personal computing component of the computer revolution."
Engelbart began work on his concept of the computer mouse in 1964, looking for a way to interact with a computer's display.
He had served in the Navy during World War II as a radar operator and recalled using a light pen, a kind of stylus fitted with a photocell to control a cathode-ray tube, the technology that powered radar systems and early televisions.
He said he believed a similar setup could work for the computer monitor.