Last year, 28.1 million mainland tourists visited Hong Kong - 67 percent of the total number of visitors, said Greg So, secretary for commerce and economic development for the special administrative region's government.
The mainland has become the largest source of tourists for Hong Kong, he said, and the number of tourists to the city is growing.
"With the opening of our harbor for cruise ships next year, we expect to offer more choices for mainland tourists," he said.
Joseph Tung, executive director of the Hong Kong Travel Industry Council, said he believes the city's flourishing tourism industry should thank the central government's rescue moves in 2003 when Hong Kong was "nearly dead" because of the SARS outbreak.
"Nobody came to visit Hong Kong then. Other countries were also afraid that Hong Kong tourists going out would spread the disease. We were really worried," he said.
When the central government decided to allow mainland tourists from some cities to visit Hong Kong without joining tour groups in July 2003, it immediately boosted tourism.
In August 2003, more than 946,000 mainland tourists visited Hong Kong, an increase of 43 percent over the same period of the previous year, according to the council.
The influence of mainland tourists on the city has been overwhelming. More people in the city's travel and retail industries have learned to speak Mandarin.
"Even when we go shopping, the salesperson, unable to tell us from mainland tourists, would speak to us in Mandarin, instead of Cantonese," said Greg So, joking that he learned Mandarin partly during shopping.
But along with the growing number of tourists, there are also a growing number of conflicts.
In 2010, Chen Youming, 65, former player of the national ping-pong team, had a heart attack and died when he was forced to shop by an unlicensed tour guide in Hong Kong.
Last year, another tour guide got involved in verbal and physical conflicts with three mainland tourists. Reports said that the tour guide led the 33-member group to a jewelry store, but none of the group bought anything during the two-hour stay. The tour guide began snarling at them.
Also last year, a video showing a mainland woman and a few Hong Kong residents arguing on the subway went viral online. The woman had let her child eat on the subway, which is not allowed in Hong Kong. The video triggered a heated discussion online.
Media comments said that the rising number of conflicts is a new trend. But Tung said these incidents are just isolated cases.
The council is doing its best to regulate the industry and tour guides to prevent incidents such as these from tarnishing Hong Kong's image, he said.
At least seven tour guides have had their licenses suspended, he said. The travel agency that hired the unlicensed tour guide who forced Chen Youming to shop lost its business license, Tung said.
Hotlines have been opened to record tourists' complaints. The number of complaints has dropped by 40 percent in the first five months of this year compared with the same period last year, he said.
Tung said he hopes the central government will allow citizens of more mainland cities to visit Hong Kong without joining tour groups.
Currently, citizens of 49 mainland cities can go to Hong Kong without joining tour groups.