Governments around the world requested information on about 38,000 Facebook users in the first six months of 2013.
Facebook's Global Government Requests Report, released on Tuesday for the first time, offered details on official requests from 74 countries.
The US made by far the most requests, asking for information on between 20,000 and 21,000 users. UK authorities requested Facebook hand over data on 2,337 users.
"We will continue to be aggressive advocates for greater disclosure," Facebook said.
"We hope this report will be useful to our users in the ongoing debate about the proper standards for government requests for user information in official investigations," wrote Facebook lawyer Colin Stretch.
"And while we view this compilation as an important first report - it will not be our last."
Unlike other countries, which had an exact figure, the US data was given as a range due to it being forbidden for companies to disclose how many requests they have had.
"In coming reports, we hope to be able to provide even more information about the requests we receive from law enforcement authorities," Mr Stretch added.