Swiatek, who will be aiming to regain the French Open title she won in 2020 when she heads to Roland Garros later this month, has won 26 matches on the bounce after a 7-6 (7-2) 6-0 triumph over Andreescu, the 2019 US Open champion.
The 20-year-old Pole has now won all nine of her matches since she became world No.1 after Ash Barty's retirement in March.
That makes her part of an exclusive club, with only Justine Henin (in 2004) and Victoria Azarenka (in 2012) having achieved that feat in the 21st Century.
Swiatek's winning streak also matches Azarenka's 2012 sequence as the fifth-longest this century. Henin and the two Williams sisters are the only players to have won more consecutive matches since the start of 2000.
"Being in that kind of group is like a dream come true for me," Swiatek, who has won 38 of her past 39 sets since her fourth-round match at the Indian Wells Open, said.
"I wouldn't think of that when I was younger. I'm pretty happy that I could do that because consistency was the thing I really wanted to work on last year. This year I feel like it clicked."
The only player to have beaten Swiatek in a tour-level quarter-final to date is Maria Sakkari, at Roland Garros last year, but the Greek saw victory slip from her grasp against Ons Jabeur.
Sakkari led 6-1 5-2 against the Tunisian, yet Jabeur rallied remarkably to claim a first career win against a top-five opponent on clay, prevailing 1-6 7-5 6-1.
After winning the Madrid Open last week, Jabeur has now won 10 straight matches, while she has claimed 16 victories on clay in 2022, leading the way on the WTA Tour.
While Jabeur will face world No.23 Daria Kasatkina, whose opponent Jil Teichmann retired when 6-4 3-2 down, Swiatek will go up against No.3 seed Aryna Sabalenka.
Amanda Anisimova had not lost to Sabalenka in four previous meetings over the past three years, but her luck ran out as she went down 4-6 6-3 6-2.