BEIJING -- Predictions that half-a-million overseas visitors would attend the Olympics accelerated a surge of hotel construction here. Now, with the Games less than a month away, all that building may have produced a glut of rooms in one of the world's prized hotel markets.

Loretta Chao/WSJ An employee at the Crowne Plaza Sun Palace, one of many hotels that opened in Beijing ahead of the Olympics.

When the Olympics start, Beijing will have more than 50 five-star hotels open for business, up from fewer than 20 just five years ago. More than 30 hotels still under construction, including at least 13 five stars, will soon provide more capacity. A Mandarin Oriental will be located at the foot of the new China Central Television tower. The Opposite House will have 99 rooms, complete with deep-soaking oak bathtubs and published rates that start at $732, double those of many of the city's most expensive hotels.

InterContinental Hotels Group PLC and Marriott International Inc., which operate two Ritz-Carlton hotels in Beijing, are among the multinational hotel companies with the biggest bets on Beijing. IHG has 13 hotels in the city, including two that have yet to open, and Marriott has 10, five of which opened in the past seven months. That compares with seven IHG hotels and 12 Marriotts in New York City, a more mature hotel market.

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"There's really been too much growth in the last couple of years," says Shaun Rein, founder of Shanghai-based market researcher China Market Research Group. He estimates the Beijing hotel industry is growing by 20% to 25% a year based on revenue and 12% to 15% based on number of visitors. By contrast, the number of luxury hotels opening in the city has grown at an average rate of 40% a year, according to the Beijing tourism bureau numbers.

The worries about a possible glut have grown in recent weeks. Many of Beijing's newest hotel rooms are sitting empty following the government's tightening of visa restrictions as part of public-safety measures tied to the Olympics. Even during the Games, occupancy rates may not be as high as originally predicted. The tourism bureau says that more than three-quarters of Beijing's five-star hotels are booked for the Olympics, but at four stars, less than half the rooms are reserved.

In fact, the Olympics appear to be doing little to boost Beijing tourism. The tourism bureau's current estimate of 400,000 to 450,000 foreign visitors for the Games next month is pretty close to the 420,000 inbound tourists Beijing received last August when the Games weren't a lure.

The hotel companies say that vacant rooms don't worry them. "While we are looking forward to the near-term exposure around the Olympic Games, we always plan for the long term, and that's why we're expanding so quickly in China," says a Marriott spokesman.

An IHG spokeswoman says that the company is also expanding with the future in mind. "In the longer term, we believe that China's hotel industry will continue to do well," she says.

Meanwhile, the owners of new hotels have other worries besides how soon guests will materialize. China has a relatively small pool of experienced service workers, and the new hotels are engaged in a brutal battle for staff.

Established hotels are already complaining of widespread poaching as the new hotels scramble to fill thousands of positions. "Elsewhere when people poach, you will normally only see one or two department heads, even the [general manager] himself," doing the poaching, says Pauline Teo, human resources director for Accor SA in China, which will run nine hotels in Beijing by the Games, including the five-star Sofitel Wanda and several budget hotels. "Over here in China, you can see a team going in and combing the place. It's like a SWAT attack."

Winnie Ng, vice president of human resources in Greater China for IHG, says the Olympics has definitely tested the company's ability to recruit and keep staff. There are benefits to IHG's large network of hotels in China, she adds, because staff from other cities will be traveling to Beijing to help this summer.

Some new hotels say they have hired their staffs from established hotels outside China, but recruiting that way has been difficult because of the decline in other currencies against the Chinese yuan.

The fight is particularly fierce for chefs and kitchen-staff spots, which require talent and experience. "With all these new openings coming up and all these five-star hotels, everybody wants people," says Anders Hallden, the executive chef at the Crowne Plaza Sun Palace, one of IHG's new hotels.

There's always a chance Beijing will spring a surprise on hoteliers and draw one million domestic and foreign visitors to town for the Games. That would turn an oversupply problem into a scramble for rooms, because the city will have only some 666,000 beds available for tourists, the tourism bureau says.

--Gao Sen contributed to this article.

Write to Loretta Chao at loretta.chao@wsj.com and Jason Leow at jason.leow@wsj.com

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