Following a renewed focus on gun violence in the US - which comes after school shootings in Texas, Florida and other states across the country - those under 18 won't be able to view certain ads on the social media network.
As reported by The Verge, the company - which already bans ads for guns and modifications - will change what audiences will be available to see on the website's marketplace.
Accessories such as gun-mounted flashlights, holsters, gun cases, gun paint, scopes and slings are all allowed to be sold on Facebook, but it won't be as simple.
A spokesperson for the site revealed sellers will be required to "restrict their audiences to at least 18 years of age or over".
Although the listed advertising policies don't currently list the age restriction, that will change once the policy is put in place on June 21.
It currently states: "Ads must not promote the sale or use of weapons, ammunition or explosives. This includes ads for weapon modification accessories."