Interviewed at a conference in Barcelona, Spain, Zuckerberg responded to a question about a document leaked by former U.S. National Security Council contractor Edward Snowden, suggesting Facebook and other companies offered the NSA unfettered access to their servers.
"The government blew it," he said, adding that NSA was "way over the line" in inadequately explaining its reasons for data collection and citizens' security. "The NSA issues, I think, are real issues for American Internet companies. Trust is so important."
The spy scandal will complicate plans to link another billion people, worldwide, to the Internet, he said.
Zuckerberg said he welcomes news of the U.S. government's attempts to be more open about the data it collects, the technology website CNET said.
"They're only now starting to get to the range of where they should have been. This thing could have all been avoidable," he said.
Facebook and several other Internet technology companies were implicated by documents leaked in 2013 that suggested the companies had participated in a clandestine NSA mass electronic data-mining program called PRISM, launched in 2007.