"Facebook had reportedly not responded to a request to remove fanpages provoking activities against the state," the official Vietnam News Agency said, citing the Ministry of Information and Communication.
In a statement, a Facebook spokeswoman said: "We have a clear process for governments to report illegal content to us, and we review all these requests against our terms of service and local law."
She did not elaborate.
The ministry said Facebook also allowed personal accounts to upload posts containing "slanderous" content, anti-government sentiment and defamation of individuals and organizations, the agency added.
"This content had been found to seriously violate Vietnam’s Law on cybersecurity" and government regulations on the management, provision and use of internet services, it quoted the ministry as saying.
Facebook had refused to provide information on "fraudulent accounts" to Vietnamese security agencies, the agency said in Wednesday’s report.
The information ministry is also considering taxing Facebook for advertising revenue from the platform.
The report cited a market research company as saying $235 million was spent on advertising on Facebook in Vietnam in 2018, but that Facebook was ignoring its tax obligations there.
In November, Vietnam said it wanted half of social media users on domestic social networks by 2020 and plans to prevent "toxic information" on Facebook and Google.