Thousands of inspectors will be on hand to enforce toughened regulations, and hand out 200-yuan (Â£21; $32) fines to anyone caught lighting up in restaurants, offices and on public transport in the capital. Businesses that turn a blind eye could be fined up to 10,000 yuan.
However, some of China's media outlets say not everyone fully understands the new law.
An online survey by the China News Service shows that 80% of the netizens who responded had "different levels of understanding of the ban", while close to 20% of the respondents "have no idea".
Other surveys had similarly pessimistic results.
A report in the China News Service finds that more than 60% of those interviewed said they would not stop other person from flouting the rules.
"I am not a law enforcer. I will invite trouble if I stop a smoker directly. If I am in a restaurant, I will change a seat or just leave," says one of the respondents.
The China Economic Net reports that many are "not confident" that entertainment venues and restaurants will remain smoke-free. It adds that both smokers and non-smokers generally agree that the fine of 200 yuan is too low for individuals.
However, some of China's prominent newspapers and websites have been trying to "educate" people about the ban.
The Sohu, a popular web portal, suggests business owners set up a separate smoking area for guests and the Beijing News urges people to help officials strictly enforce the ban.
Despite the challenges, an opinion piece in the China Daily says the new regulations are "a good beginning to create a smoking-free world" and will "test the authorities' determination, responsibility and administrative ability".
For the Beijing Times, the ban is the "first strong step" in Beijing and it is likely to set a good example for others.
The "toughest ban" has indeed served as an inspiration for others to follow, it says.
According to Chengdu Evening News, Chengdu, in southwest Sichuan province is also considering a similar set of regulations to deter public smoking.
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A new law has come into effect in China's capital, Beijing, banning smoking in public places.