The social media outage began at about 4pm BST, according to the website Down Detector.
The problem has also hit WhatsApp and Instagram.
The outage tracking website showed that there are more than 9000 incidents of people reporting issues with Facebook, reports Reuters.
The outage has hit Bangladesh, Malayasia, Myanmer, UK, France, Germany, the Czech Republic and Poland, the site reports.
Thousands of people have reported outages in the last hour.
Pages are either not loading, or users are unable to post.
Some British users have been hit by the WhatsApp outage, that has hit Italy and the Netherlands most severely, Down Detector also reports.
Meanwhile Instagram is down in Britain, Paris, Berlin, Italy and Greece.
One user said: "Instagram, Facebook and WhatsApp are down. Thank you Zuckerburg, great service."
A second chipped in: "Facebook, we have a problem."
While a third joked: "Facebook's down, we all gonna die. Or I'll just go and walk the dog."
Facebook had experienced one of its longest outages in March, when some users around the globe faced trouble accessing Facebook, Instagram and WhatsApp for over 24 hours.