Around 18 people in every 100,000 in Scotland are diagnosed with malignant melanoma annually compared to just four in 100,000 40 years ago, new figures from the charity show.
On average 1200 people are now developing the most serious form of skin cancer every year - compared with about 190 in the mid-1970s.
The figures were revealed as the charity launches a new campaign to encourage people to look after themselves in the sunshine.
A charity spokesman said: "The rise is partly down to an explosion in package holidays to Europe dating from the late 1960s and the increasing popularity of the must-have tan, often achieved only after damaging sunburn.
"The boom in sunbed use has also helped to fuel the increase in skin cancer, and better detection methods may also have contributed to the increase in the number of people diagnosed."
Malignant melanoma is now the fifth most common cancer in Scotland.
Mother-of-three Caroline Begg, from Glasgow, offered her support to the campaign after fighting malignant melanoma.
The receptionist used sunbeds before being diagnosed eight years ago aged 26. A mole on her back prompted her to go to the doctor and she said she is lucky the cancer was picked up early.
Ms Begg, 34, said: "I have a large scar on my back but that's nothing compared with what could have happened. I could have ended up not being able to have children. I could have died.
"I was aware that the sun could age your skin but didn't even think about skin cancer. I'm fair skinned with freckles and moles so I'm actually in a high risk category."
The mother of 13-week-old Nicholas, two-year-old Isabelle and four-year-old Oliver said: "I make sure my kids don't stay out in the sun too long, always use sun cream and I try to put special sun suits on the children in the summer too."
The Cancer Research UK and Nivea Sun campaign advises people to stay out of the sun when it is at its strongest, usually between 11am and 3pm.
It recommends wearing a wide-brimmed hat, a T-shirt and sunglasses when in the sun and protecting exposed skin with sunscreen with a minimum of factor 15.
Chloe Cowan, a Cancer Research UK nurse based at the Beatson Cancer Centre in Glasgow, said: "Everyone loves getting out and about and enjoying the summer sun. It's essential to take care not to burn. Sunburn is a clear sign that the DNA in your skin cells has been damaged and, over time, this can lead to skin cancer.
"When the sun is strong, pop on a T-shirt, spend some time in the shade and use a sunscreen with at least SPF15 and good UVA protection."
Lisa Adams, Cancer Research UK spokeswoman for Scotland, said: "We know overexposure to UV rays from the sun or sunbeds is the main cause of skin cancer. This means, in many cases, the disease can be prevented, so it's essential to get into good sun safety habits, whether at home or abroad.
"Sadly more and more people in Scotland are being diagnosed with malignant melanoma each year. But the good news is that survival is amongst the highest for any cancer. More than eight in 10 people will now survive the disease."