The birth Wednesday was the first of the species in Europe, Jonas Wahlstrom, managing director of the aquarium at Stockholm's Skansen animal park, said.
"We're extremely happy to have finally succeeded in multiplying the numbers of Gila monsters after breeding them for years," he said.
The reptiles were born after a four-month incubation period, the Swedish news website TheLocal.se reported Sunday.
The Gila monster is native to the southern United States and northern Mexico. One of only two species of poisonous lizards, it can grow to as long as 24 inches.