Slovakia's Magdalena Rybarikova didn't offer much resistance in her 6-1, 6-1 loss to Muguruza.
Saturday, Williams will attempt to become the oldest woman to win a Grand Slam tournament since professionals were first allowed to play them in 1968, breaking the mark set by her younger sister Serena at the Australian Open in January.
Svetlana Kuznetsova proved even less of an obstacle as Muguruza sent the No7 seed packing in just 75 minutes, never once dropping her serve.
Konta was the first British woman to reach the semi-finals since Virginia Wade in 1978.
World number 11 Williams, beaten in this year's Australian Open final, was knocked out in the 2016 semi-finals and is chasing a first major title since winning Wimbledon in 2008.
"You have to protect yourself and put up a barrier so that you don't let them impose themselves on what has been so good with her concentration and her game plan". In addition, after not reaching the quarterfinals since 2010, the five-time Wimbledon champ has now followed up a semifinal showing a year ago with either a title or a final this time around. This will be her second trip to the Wimbledon finals in three years.
Fittingly, Williams finished proceedings with a booming forehand that was typical of the power that got her over the line. I mean, I know she acts like this all the time. "It won't be a given but I'll give it my all".
"I think a lot of things are also clicking with her and the team this week, so it's very nice".
It was only then, with the first set effectively gone, that Rybarikova started to play anything vaguely resembling tennis that has got her this far.
"Serena is always in my corner and usually it's her in these finals, so I'm trying my best to represent Williams as best as I can". But I felt really comfortable out there, Venus just played better than me.
Another wayward backhand from the Slovak gave Muguruza a second break and, presented with a 4-0 lead, the Spaniard closed out the set in emphatic style. "Of course, I'm excited about being again in another final", the 37-year-old, bidding to become the oldest player to win a Grand Slam in the Open Era, said.
Rival Garbine Muguruza the Wimbledon final will be determined in a few hours.
In this series of Wimbledon both the players won five matches in four rounds and Quarter Finals.
Johanna Konta of Britain hits a shot during against Venus Williams.