Chinese investors' appetite for overseas commercial real estate is unrelenting, and the United States is the top destination for that investment, according to a recent survey by CBRE, a Los Angeles-based commercial real estate firm.

The survey found that China's expenditure on US commercial real estate in the first half of 2015 was $3.68 billion, doubling last year's figure.

In the past two and a half years, about $2.98 billion has been invested into the US hotel industry, the research showed.

China accounted for more than one quarter of total outbound commercial real estate investment from Asia during 2013 and 2014, the survey said. About 20 percent of that went into US properties.

A report by JLL, a real estate agency, said that China spent $5 billion on overseas hotel purchases in the first eight months of 2015.

In October 2014, Beijing-based Anbang, a life, health and property insurance company, purchased New York's landmark Waldorf Astoria hotel for $1.95 billion.

This past October, three Chinese companies competed for the Starwood Hotel, a US hotel chain.

Shanghai-based Jin Jiang International Group Co Ltd, a Chinese state-owned hotel chain, made several purchases of overseas hospitality companies.

According to a report on China outbound tourism development in 2015, at least 107 million Chinese citizens traveled overseas in 2014, doubling the number of outbound Chinese travelers in 2009.

Experts said the increasing number of Chinese outbound visitors contributed to the investment spree.

Li Fei, a professor of economics in Tsinghua University, said most Chinese investors and financial groups are looking to get a share of the ever-increasing purchasing power of Chinese visitors from abroad.

"Many Chinese visitors are traveling, and that makes overseas hotels desirable and worth investing in," Li said.

According to a report co-published by the Fung Business Intelligence Center and China Luxury Advisors, Chinese visitors' overseas consumption value will exceed $420 billion by 2020.

Another report by JLL indicated that Chinese investors in the hotel industry are pursuing a more diversified portfolio rather than solely relying on domestic Chinese hotels.

According to the report, return on investment in the Asia-Pacific hotel industry has continued to tighten in the past 15 years, falling from 9 percent in 2011 to 6.25 percent in 2015.

The short-term market performance sentiment in Chinese cities like Beijing, Shanghai and Hong Kong also has dimmed, making countries such as Australia and the US attractive for foreign capital.

"Most of the hot spots are San Francisco, New York in the US, Vancouver in Canada, Paris in France, Seoul in South Korea and Bangkok in Thailand", said Zhang Zhuyun, the manager of Guangzhou Dongfang Hotel Group.

The EB-5 visa program also plays a role. The US government program grants green cards to investors of $500,000 to $1 million (depending on the location) who create or maintain jobs.

Dictson Fu, a financial adviser for Morgan Stanley, said EB-5 fueled investor preference for overseas hotels because it also can provide working opportunities for the investors.

Fu said the US authorities have prohibited some Chinese acquisitions for "national security reasons".

Most of the restricted areas for Chinese investors were semiconductors, telecommunications and transportation infrastructure, Fu said.

"Therefore, buying the hospitality industry like hotels faces less national scrutiny than the highly political, risky acquisitions," he said.

Long Yifan in New York contributed to this story.