The dog's owner managed to take a photo of the snake, which animal control officers identified as an albino monocled cobra.
The dog was taken to an animal hospital in critical condition.
Arsinian says albino monocled cobras are illegal to own.
The snakes are common in southeast Asia and can grow to more than 4 feet long.
Thousand Oaks is in area of Ventura County serviced by Los Angeles County animal control.