Noskova dominated from start to finish in a last-eight clash lasting one hour and 50 minutes in searing temperatures on Court One.
In only her second Grand Slam quarter-final, following her run at the 2024 Australian Open, Noskova sealed a place in the last four of a Grand Slam for the first time.
In the lead-up to Wimbledon, Noskova won the Berlin Open, her first grass-court title.
She has taken that impressive form into the All England Club, dispatching former Australian Open champion Madison Keys in the last 16 before brushing aside Mertens.
Having reached the fourth round at Wimbledon last year, Noskova is now just one win away from her maiden Grand Slam final.
"The feelings are incredible, like never before. This is what I am playing tennis for, these big stages and big matches," she said.
"I was a little bit nervous before the match, I am not going to lie. When I am putting pressure on myself that is usually when I play my best. I really enjoyed this match."
Mertens, 30, had been hoping to make the Wimbledon semi-finals for the first time, but the 25th seed bowed out after a strong run featuring a win over second seed Elena Rybakina.
21-year-old Noskova faces Ukrainian 12th seed Marta Kostyuk in Thursday's semi-finals.