Dorset and Wiltshire Fire and Rescue worked with Mendip Cave Rescue to free them from the former stone mines in Box after being called at 02:50 BST.
Martin Grass, from Mendip Cave Rescue, who helped rescue the seven, in their late teens and early 20s, said they were "cold and inadequately equipped".
It comes after another group had to be rescued from the same caves on Sunday.
Nobody in either group was injured but the fire service is warning people "to think twice before visiting the former stone mines".
Mr Grass said: "With these two most recent rescues, the groups were woefully ill-equipped for what they were trying to do, and they were very lucky that they found a place of relative safety where there was a phone signal."
After rescuing another group of three men on Sunday evening, the fire service tweeted saying that signs, to help people get out, had been painted over.
Darren Nixon, from Dorset and Wiltshire Fire and Rescue said: "Fortunately, nobody was injured on these two latest occasions, and the groups were OK to stay where they were until the cave rescue team arrived.
"However, with a bit more planning, and a bit more thought, they could have avoided multiple fire crews and volunteers being mobilised.
"Having fun is fine, but please think twice about your plans and whether you have done everything possible to be safe."
In July last year, a group of teenage boys had to be rescued from Box mines after getting stuck 100ft underground while paying the smartphone game Pokemon Go, where users search real-life locations for digital creatures.

The White Rabbit, the Cheshire Cat and Alice all feature in artist Grahame Baker-Smith's illustrations.
The story was made up by Charles Lutwidge Dodgson, a young don at Christ Church in Oxford, to entertain children on a boat trip in 1862.
It was published under Dodgson's pseudonym, Lewis Carroll, three years later.
One of the children on the Thames boat trip was Alice Liddel, the daughter of the dean of the college.
Alice later asked for the story, originally entitled Alice's Adventures Under Ground, to be written down. Dodgson did so as a Christmas gift in 1864 with his own illustrations.
It went on to become one of the best known works in children's literature, with numerous TV and film adaptations.
The stamps feature famous scenes from the book including the Mad Hatter's tea party and Alice falling down the rabbit hole.
Illustrator Grahame Baker-Smith said he had based the images of Alice on the stamps on his own daughter.
"The most difficult thing was consistency and working on such a very small scale. They all have to work as a set, so you want to have a range of colour and tone across the 10 stamps.
"The Royal Mail has a rich history of illustration on stamps, so the chance to have a go at that is a great opportunity."
Andrew Hammond, Royal Mail director of stamps and collectibles, said: "The story of Alice in Wonderland remains a perennial favourite of children, and indeed adults, around the world.
"It is fitting that in its 150th anniversary year it is celebrated with a wonderful set of stamps featuring striking images that do justice to such an iconic tale."
Firefighters have rescued a group of people trapped in a Wiltshire cave for the second time in a week.
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A set of 10 stamps is being issued to mark the 150th anniversary of Lewis Carroll's Alice in Wonderland.