The incident occurred shortly after 4 p.m. local time along the popular, scenic cliffs near Southerndown in the Vale of Glamorgan, Wales Online reported.
"It's not being treated as suspicious and it appears to be a tragic accident at this stage," a South Wales police spokeswoman said.
The couple had not been identified, but authorities said the man, who was dead at the scene, was 27 and the woman, who was hospitalized in stable condition, is 25.
Wales Online said witnesses screamed when they saw the couple fall.
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