The Ontario Medical Association (OMA) wants the government to put higher taxes on junk food.
Doctors say that higher costs would make it harder for children to buy junk food.
They also want high fat and sugary foods that have little nutritional value, to have more information and even warnings on the packaging.
And they want less junk food advertising, especially targeting children.
These are just three strong actions doctors say will help children eat less junk food, keep their weight at a healthy level and live a longer life.
The Ontario Medical Association said that over the years strong actions like extra taxes and scary pictures on cigarette packages have helped to reduce smoking from 50 per cent, in the 1960s, to as low as 20 per cent in Canada today.
Doctors say this kind of action can help in the same way with junk food.