Swiatek gets 'goosebumps' after reaching first Wimbledon semi-final
The Polish eighth seed will face Russian teenager Mirra Andreeva or former Olympic champion Belinda Bencic for a place in Saturday's final.
Swiatek has won four titles on the clay at the French Open, as well as the US Open in 2022, but has struggled on the lawns of the All England Club.
Her previous best result at Wimbledon was a run to the quarter-finals in 2023.
Swiatek dominated the first set against 19th seed Samsonova on Court One but was made to battle in the second set before wrapping up victory in one hour and 49 minutes.
"It feels great. Even though I'm in the middle of the tournament I've already got goosebumps after this win. I'm super happy and super proud of myself and I'll keep going," she said.
"Honestly, I've really enjoyed playing this year and hopefully it's going to last as long as possible.
"For sure I feel like I really worked hard to progress here on this surface."
Swiatek broke twice in the opening set to take a firm grip on the match, benefiting from a flurry of unforced errors from her opponent and winning 100 percent of her points on first serve.
Two double faults from the Russian 19th seed handed Swiatek an early break in the second set and she snuffed out a clutch of break points in the following game to go 3-0 up.
The 24-year-old was pegged back as her level dipped and Samsonova pulled level at 4-4.
But Swiatek regrouped and broke again to seal the win, finishing off her opponent with a fierce forehand winner.
The former world number one has gone under the radar at this year's Wimbledon as most of the other top women's seeds have tumbled, though world number one Aryna Sabalenka is still standing.
After slipping down the rankings, she is now back in the world's top four having reaching the Bad Homburg final on grass last month.
Swiatek, a former Wimbledon junior champion, lost in the semi-finals of both the Australian Open and the French Open this year.