The four reptiles were born last month from a clutch laid at London Zoo by a female called Sungai.
Sungai normally lives at the Thoiry wildlife park, west of Paris, but was lent to London as part of a European breeding program to help the endangered species.
But Sungai laid the fertilised eggs before even meeting her British lover - and the last time she is known to have had sex was two years ago, with another Thoiry Komodo dragon called Kinaam.
The founder of Thoiry wildlife park, Paul de la Panouse says that there are two possible answers to the riddle.
"Either female komodo dragons are spermthecal, meaning that they have the ability to store sperm or fertilised eggs for long periods, in this case for two years, or they are parthogenetic, meaning that they are self-reproductive -- they produce clones of themselves," Mr de la Panouse said.
Genetic tests will be carried out to try to explain the mystery.
The Komodo dragon is the world's biggest lizard, reaching up to three metres in length.