Hong Kong residents who boo the Chinese national anthem might soon face up to three years in prison.
China's parliament, the National People's Congress, is extending a law on disrespecting the anthem to semi-autonomous Hong Kong and Macau.
Hong Kong's government, dominated by Beijing loyalists, has begun including it in local legislation.
The anthem has been booed at recent football fixtures in Hong Kong, where anti-Beijing sentiment has been rising.
Democracy activists fear the new law could be used to undermine freedom of expression in the territory, which enjoys freedoms not seen on the mainland.
Hong Kong, a special administrative region of China, has a separate legal system so it is too early to say whether the punishment for mocking the anthem will be as severe as the current Chinese law, the BBC's Juliana Liu in Hong Kong says.
The new law, enacted by China in September, is expected to pass Hong Kong's legislature without difficulty.
Protesters concerned about what they see as Beijing's increasing control over the territory, have been booing the anthem since 2015, notably at a World Cup qualifier against Qatar.
In October, Hong Kong fans turned their backs as the anthem was played during at a qualifier against Malaysia and some spectators jeered and made rude gestures before a friendly match against Laos.
Jeering the anthem is the latest salvo in a series of protests that grabbed international attention in 2014 when major thoroughfares in Hong Kong were occupied for weeks in a push for full democracy.
Hong Kong, formerly a British colony, returned to Chinese rule in 1997 under an agreement which is supposed to guarantee the territory's people basic rights.