The Legislative Council Finance Committee of Hong Kong?approved HK$66.9 billion (US$8.6 billion) in funding for the controversial express rail link to Guangzhou on Saturday.
The Guangzhou-Shenzhen-Hong Kong Rail Link will form part of China's national high-speed rail network and allow people to travel from Hong Kong to Guangzhou in 48 minutes, just under half the amount of current journey time.
The project is expected to be finished by 2015.
Pan-democrats tried to delay the vote by asking multiple questions and proposing 27 motions - none of which were allowed to go forward. The funding was approved by 31 votes to 21.
On Saturday, hundreds of angry protesters surrounded the legislature to show their opposition to the project, sparking violent scenes with riot police, and affecting traffic for several hours.
Some lawmakers said the government had not properly consulted the public and protesters said there was little consideration of other alternatives.
Tam Yiu-chung, Democratic Alliance for the Betterment and Progress of Hong Kong legislator, said that the accusation was unfair.
"We have spent 10 years doing research and assessment on the project. We are lagging behind the mainland's progress in terms of the construction. We have to set the wheels in motion as soon as possible," Tam said.
Secretary for Transport and Housing Eva Cheng said the high-speed railway was important for enhancing ties between Hong Kong and other major cities on the mainland.
Executive Council convenor Leung Chun-ying said on a radio show that the government would consider whether it's possible to reclaim less land for its construction.
The Chinese Manufacturers' Association of Hong Kong released a statement in support of the Express Rail Link.
The statement points out that the completion of the rail link would help Hong Kong tackle the economic crisis, allow large numbers of passengers to go to Hong Kong and enhance interactions with the mainland.
The project did not attract much attention in 2008 when debated by the Legislative Council. Then, the majority of lawmakers supported the proposal that the terminal to be located in West Kowloon, but they changed their minds when they found out that the cost was higher than originally estimated, Tam said.