The Lynchburg News & Advance reports Falwell was pronounced dead at Lynchburg General Hospital after he collapsed in his office.
Ron Godwin, executive vice president of Liberty University, said Falwell was found unconscious about noon after missing a morning appointment, the newspaper said.
Falwell has been credited with forging theological and social conservatives into a powerful electoral bloc often referred to as the "Moral Majority."
He started his Thomas Road Baptist Church in 1956 with 35 members in the abandoned Donald Duck soft-drink bottling plant on the west side of Lynchburg, where he was reared.
The church in 1987 had about 20,000 members.
In his television sermons, Falwell lashed out against immorality, liberalism, communism, gay rights, pornography, abortion, the welfare state, sex education in schools and the Equal Rights Amendment.
Falwell was born Aug. 11, 1933, in Lynchburg. His father, Carey, was a successful businessman who had a drinking problem and died in 1948 of cirrhosis of the liver.
He is survived by his wife of 49 years, Macel, and three children.