|Venus Williams vs Johanna Konta|
Sixth seed Konta, 26, had hoped to become the first British woman in a Wimbledon singles final since 1977.
She will break into the top five for the first time in the next rankings.
Williams is the oldest Grand Slam singles finalist since Martina Navratilova finished runner-up at Wimbledon in 1994.
The American, through to her ninth final, won her first Wimbledon title in 2000 and the most recent of her seven major victories came on Centre Court in 2008.
"I've played a lot of finals here," Williams told BBC Sport. "One more win will be amazing. It won't be a given but I'll give it my all."
She will next face Muguruza, the 14th seed, who thrashed unseeded Slovakian Magdalena Rybarikova 6-1 6-1 in just 64 minutes to advance to her second Wimbledon final.
The Spaniard finished runner-up to Serena Williams in 2015, before beating the American to win the French Open in 2016.
'The crowd were very nice to me'
In a tight contest between two of the best servers in the game, Williams worked her way to victory with smarter serving and more effective returns.
The American, playing her 20th Wimbledon, showed all her experience to edge out Konta and end British hopes in this year's singles events.
It was Konta under the greater early pressure at 30-30 or deuce in her opening four service games, with Williams stepping in to attack the second serve, but the Briton calmly played her way out of trouble.
Konta then earned the first two break points of the match at 4-4 but it brought the best out of Williams, who produced a backhand winner, a 106mph second serve and a forehand winner.
The former world number one would carry that momentum through the rest of the match, finding big second serves and aiming at the body to restrict Konta to just 13 points on the return as her forehand in particular leaked errors.
Konta fell 0-40 down to offer up three set points in game 10, firing a backhand long on the second, and Williams got the decisive break at 3-1 in the second.
There was no chink of light on the Williams serve for the home crowd on Centre Court to get excited about, and Konta could only watch as the American arrowed a forehand past her down the line on her third match point.
"The crowd were very nice to me," added Williams. "The crowd were so fair, I know they love Jo. I think Jo handled the pressure.
"No point was easy. I tried to climb on top and get another point." PLACE YOUR TEXT ADVERT BELOW:>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> How I TOTALLY Got Rid Of my POT BELLY,excess Fat and Overweight In just 2weeks.. Click HERE for Details.