E-cigarettes, or vaping, is set to be banned in all areas where cigarette smoking is prohibited in Victoria, under new laws to come into effect next year.

Under the changes, e-cigarettes will be treated like other tobacco products and children under 18 will no longer be able to buy them.

Victorian Health Minister Jill Hennessy said vaping could be a gateway to smoking for young people and the laws would give more clarity to workplaces and restaurants.

"We're going to regulate them like they are a tobacco product and also make sure that we're not really using e-cigarettes as a starting point for people to get a habit to then start cigarettes and then get addicted to nicotine," she said.

"We don't want e-cigarettes being used to glamorise smoking by people under 18."

Ms Hennessey said while the exact health risks of vaping were not clear, about 4,000 Victorians each year die from tobacco-related illness.

"In the absence of having really clear evidence about this, we've decided to take a really cautious approach," she said.

"Whilst there is some debate about whether or not e-cigarettes are useful in giving up smoking, and that's a matter that the smoking experts are not really unified on at the moment, we don't want e-cigarettes used to glamorise smoking.

"We want to give certainty to people who don't know whether or not e-cigarettes should be allowed to be used in enclosed workspaces and at restaurants, people walking through airports for example with e-cigarettes."