Google was asked by Brazilian officials to remove content from the web 398 times in the first half of the year, the most by a government, according to a report by the internet-search company.
Brazil's requests were more than double the total from Libya, which came in second with 149.
The US and Germany followed with 128 and 124 requests, respectively, Google said in its second report on government transparency which lists 35 countries that make such demands.
Google, owner of the world's largest search engine, aims to share information about its dealings with governments to promote free expression and competition in emerging internet markets.
Google closed its search engine in China earlier this year after clashing with the country over censorship.
Users in China are now redirected to its Hong Kong site.
"We care about this because we care about free expression as a value," Niki Fenwick, a spokeswoman for Google, said.
"We also care about it because it's core to our business. When our services are blocked or filtered, we can't serve our users."
In addition to ranking the number of government requests to remove content and plotting them on an interactive map, Google yesterday opened access to a new tool that graphs the traffic of web users in individual countries.
If traffic drops off, Google plans to add notes to the site explaining whether the interruption is the result of government blocking or from a technical glitch, Fenwick said.
Access to Google's website in China became briefly unavailable in July, causing some news outlets to speculate authorities there had completely blocked access to the site.
The service became available again to Chinese users the same day, and the company said the problem may have been a measurement error.
Many requests to remove content from Brazil, where Google's Orkut social-networking service has the most users, are related to people the government alleges committed crimes of impersonation or defamation, Google said.
Earlier this year, a Brazilian court ordered the removal of more than 18,000 photos from Google's photo site, Picasa, after a lawsuit claimed they contained images from copyrighted books, Google said.
Brazil also topped Google's list of government requests for the second half of 2009, issued in April. So-called takedown requests in the country rose 37 per cent in the first half of 2010 from the previous six months.