Neth Pheaktra, an environment ministry spokesman, said that the 18-month-old male, weighing 70 kilogramnes, had been imported from overseas by the owner.
"Cambodian authorities started investigating the pet lion since they saw it on TikTok in late April," Pheaktra explains.
The owner had shared a photo on the app, in which the lion can be seen sitting on the road and a dog playing nearby.
Pheaktra said that people have no right to raise rare wildlife animals as pets.
Wildlife Alliance helped authorities rescue the lion a day after a Twitter user posted an aerial shot of the animal roaming around in the garden.
It is not yet confirmed whether the owner will face any legal action.