It said the Swiss economy has been more competitive than the economies of all other countries in each of the past nine years. In 2008, Switzerland finished in second place, after the United States.
The WEF, which is based in Geneva, produces a yearly report on economic competitiveness. The ratings are based on over 10 measures of competiveness and opinions of business leaders.
Economist Thierry Geiger works for the group. He says "Switzerland had a virtuous circle of infrastructure, institutions and education." He adds that its success came from its ability to create and use talent.
"That is really the secret of Switzerland, this ability to innovate," he says, noting that there are many things fueling creativity.
However, after almost 10 years at the top of the WEF ratings, Switzerland faces a new risk. Its population is aging. And Geiger fears that voters may decide to restrict the number of foreigners working in the country.
Switzerland holds public referendums about four times a year. The votes are part of a tradition of direct democracy. But Geiger describes some of the planned referendums as dangerous. He fears they could threaten Switzerland's economy.
The World Economic Forum is perhaps best known for its meeting of powerful people every January in Davos, Switzerland.
Klaus Schwab, the founder of the WEF and its chairman, wrote in a statement that he believes that competitiveness will depend on the ability of a country to innovate.
The top 10 countries in the latest list are the same as last year, but the order has changed. The United States moved in front of Singapore, rising from third to second place. Hong Kong moved up three places to sixth place, passing both Britain and Japan.
The WEF says that Britain has not yet felt the effect of its vote to leave the European Union, but will in the future.
China was rated as the 27th most competitive economy in the world. Russia was in 38th place, while India was 40th.
Yemen, a poor country now in a civil war, was 137th.
Top Ten Countries
2) United States
6) Hong Kong
8) United Kingdom