Jeremy Caprio says he was beaten up by a British United Nations peacekeeper outside a nightclub in the resort of Ayia Napa.
A British soldier, identified by a witness, has been confined to barracks in Nicosia, UN sources said.
Mr Caprio, 35, from Thornton, Lancashire, told The Times newspaper that the attack was unprovoked.
"I didn't have a chance. I tried to get up a couple of times but I was unconscious when I hit the floor," he said.
"The last thing I remember was a boot coming into my face."
Doctors at the private Olympic Napa clinic said Mr Caprio's condition was stable after eye surgery.
Dr Antonis Tsokkos said: "Unfortunately he suffered a rupture of the globe of the eye and he has lost his vision in the right eye."
Mr Caprio was with his sister Lisa and cousin Paula when he was attacked outside the Carwash disco.
His sister said: "He'd just come out of the club by himself and was looking for me when about three or four of them started on him."
A local police officer said a witness had identified a soldier who allegedly hit Mr Caprio.
A Ministry of Defence spokesman said: "We can confirm that an alleged assault by a British soldier serving with the UN force in Cyprus is being investigated by serving police."