Thor, a lion cub at Dehiwala National Zoological Gardens, is currently infected with the Covid-19 virus, according to zoo officials.
The animal had been sick for about three days, with a cough and sore throat, according to preliminary tests.
Thor, who was sick, was later diagnosed with PCR and is being quarantined elsewhere in the zoo.
In 2012, this animal was imported from Korea to Sri Lanka.
Workers on Lion Island have been quarantined after it was confirmed that the male lion was infected with Covid.
A lioness named Sheena and four other lions were with Thor in the lion den and PCR tests are to be carried out on these animals as well, according to the zoo authorities.
A hippo and a zebra calf have also died suddenly at the Dehiwala Zoo a few days ago and it is suspected that the two animals also died of corona, officials said.