Can disinfectant kill fleas

Dish liquid, particularly Dawn Dish Liquid is useful in killing fleas on both dogs and cats. It is particularly recommended for animals too young for flea medication and shampoos. Dish liquid, however, can be irritable to the skin and should only be used if necessary. When using any dish liquid, the animal should be rinsed several times with water to make skin irritation less noticeable.

On a dog, no. It can cause irritation and will not kill the eggs. Try dog flea shampoo or even baby shampoo