According to the website downdetector.com, the outage began around 1600 GMT, and appeared to last less than an hour.
"Earlier this morning, some people had trouble accessing Facebook for a short time," the California-based Internet titan said in reply to an AFP inquiry.
"We quickly investigated and are currently restoring service for everyone. We're sorry for the inconvenience."
Facebook had yet to pinpoint a cause, but the trouble appeared to be a technical issue.
During the outage, thousands of users complained they could not access the world's biggest social network.
Similar to the June incident, Facebook users took to Twitter to vent or post sardonic comments, many using the hashtag #facebookdown.
"Facebook is Down?! Oh God! Now How the Hell Am I Going to Find Out How My Friends Feel About Facebook Being Down?!" one user tweeted.
Another wrote "Facebook going down for 15 minutes is proof that today's generation wouldve survived approximately 8 seconds in the 80s."
A Twitter user with the handle @TheTweetofGod wrote, "#facebookdown. Please remain calm and do not attempt to interact with human beings."