Number One Plus, a water-based lubricant produced by health organisation Population Services International (PSI), is an excellent cure for acne, 29-year-old vendor Tep Kemyoeurn told AFP.
"After I used it for three days, all of my acne dried up and went away," she said. "Many people believe in it," she added.
Khen Vanny, 29, from Phnom Penh, told AFP that women of all ages have taken to using the lubricant to get rid of spots.
"It is very effective. Some people don't believe in it but people who do really get a good result," she said, adding: "My youngest sister and my aunt use it too."
Another woman told Khmer-language Kampuchea Thmey newspaper that she had used many kinds of medicine to treat acne but none had worked.
"After that my friends, who work at garment factories in Phnom Penh, advised me to apply the lubricant from Number One Plus condoms on my face every night," she told the paper.
"And just within three to four nights, the acne on my face gradually and then totally disappeared," she added.
A vendor near a factory in the coastal city of Sihanoukville told the newspaper that she sold packets of Number One Plus lubricant for 500 riels (12 cents) to many women every day.
The paper urged experts to conduct research about the phenomenon.
PSI were not immediately available for comment on the apparent cosmetic benefits of their product.